22nd June 2015 - WordPress.comSurface!Science!Day!@!UCLan,!!...

at University of Central Lancashire

22nd June 2015

Abstract Book

Surface!Science!Day!@!UCLan,!!University!of!Central!Lancashire!22nd!June!2015!

!

Sponsors!!!!!

scanwel.co.uk!

Solid!Surfaces!

Group!

rsc.org!

pspvacuum.co.u

k!

Thin!Films!and!

Surfaces!Group!

tfsg.iop.org!


!

Day!schedule!

09:00$ Coffee!(Scholars)!Chair:'Joe'Smerdon,'UCLan'

9:30$ Robert!Walsh! UCLan' Welcome/Introduction$from$the$Director$of$Research$

09:35$ Rasmita!Raval!University'of'Liverpool'

Porphyrin$Assembly$at$Surfaces:$From$SubBMolecular$Imaging$to$OnBSurface$Synthesis$

of$Oligomers$

10:10$Ronan!

McGrath!

University'of'Liverpool'

Surfaces$of$quasicrystals$and$related$complex$metallic$alloys$

10:45$ Coffee!(Scholars)$Chair:'Vin'Dhanak,'University'of'Liverpool'

11:15$ Phil!Woodruff!University'of'Warwick'

Quantitative$adsorbate$surface$structure$determination$

11:50$Chris!

McConville!

University'of'Warwick'

Electronic$Structure$and$Properties$of$Transparent$Conducting$Oxide$

Semiconductors$

12:25$Philip!

Moriarty!

University'of'Nottingham'

Pauli's$principle$in$dynamic$force$microscopy:$Do$we$really$see$chemical$

bonds?$13:00$ Buffet!lunch!and!poster!session!(Scholars)$

Chair:'Hem'Raj'Sharma,'University'of'Liverpool'

14:45$ Peter!Beton!University'of'Nottingham'

Molecular$adsorption$and$organisation$on$boron$nitride$and$molybdenum$disulphide$

15:20$ Werner!Hofer!Newcastle'University'

Dynamic$processes$observed$by$scanning$tunnelling$microscopes$$

15:55$ Robert!Jones!University'of'Nottingham'

Structural$Studies$of$Thin$Films$$10B100s$Å$thick$

16:30$ Coffee!(Scholars)$Chair:'Karen'Syres,'UCLan'

17:00$ Wendy!Flavell!University'of'Manchester'

Unravelling$the$mysteries$of$solar$nanocells$B$surface$and$interface$chemistry$in$

quantum$dots$

17:35$Andrew!

Hodgson!

University'of'Liverpool' Water$structures$and$the$wetting$of$metals$

18:10$ Poster!prize!and!closing!remarks$


Poster'list'!

P01$ Ovidiu$Crisan$

National$Institute$for$Materials$Physics,$

Bucharest,$Romania$and$University$of$Leicester,$UK$

SurfaceBfunctionalized$Cluster$Aggregated$Nanoparticles$

P02$ Simon$Smalley$ UCLan$ Adsorption$of$DBBA$and$Coronene$on$Ag(100)$

P03$ Andrew$Williamson$ University$of$Manchester$The$effects$of$Oxidation$on$the$Shell$Structure$of$Type$II$Colloidal$Quantum$Dots$

P04$ John$Hodgkinson$ University$of$Salford$SubBMicrosecond$Pulsed$Plasma$Surface$Modification$as$a$Combinational,$all$Atmospheric$Pressure$Approach$to$NanoBstructured$Thin$Film$Production$

P05$ Luis$M.$A.$Perdigao$ University$of$Warwick$Development$of$electrospray$source$for$deposition$of$large$molecules$for$STM$studies$

P06$ Gareth$Chumbley$ University$of$Nottingham$Investigation$of$Ionic$Liquids$for$stabilising$Sulphur$Dioxide$on$a$Cu(111)$surface$using$XBray$and$UltraBViolet$photoelectron$spectroscopy.$

P07$ Joshua$S.$Gibson$ University$of$Nottingham$ Stabilisation$of$CO2$within$the$Ionic$Liquid$[C8C1Im][BF4]$

P08$ Jonathan$Blohm$ University$of$Warwick$Seeing$Beyond$the$Image:$Peptide$Mass$Spectrometry$and$STM$

P09$ James$O'Shea$ University$of$Nottingham$UHV$compatible$electrospray$deposition$for$the$deposition$of$complex,$fragile$and$nonBvolatile$molecules$on$surfaces$

P10$ James$Lawrence$ University$of$Warwick$STM$Study$of$2D$SelfBAssembled$KetoneBbased$MetalBOrganic$Structures$

P11$ Stuart$Thorn$ University$of$Liverpool$Growth$of$Pb$on$the$Threefold$Surface$of$a$AgBInBYb$Quasicrystal$

P12$ Mike$Hardy$ Queen's$University$Belfast$Consideration$of$the$Coffee$Ring$Enhancement$Factor$for$More$Comparable$Surface$Enhanced$Raman$Scattering$(SERS)$Measurements$

P13$ Evangelos$Liamas$ University$of$Strathclyde$ The$effect$of$surface$chemistry$on$protein$adsorption.$

P14$ David$Connell$ University$of$Strathclyde$Physicochemical$Characterisation$and$Analysis$of$Peptide$Adsorption$Onto$Inorganic$Surfaces$for$Use$in$Immunotherapies$

P15$Sebastiaan$Van$

Nuffel$University$of$Nottingham$

3D$TOFBSIMS$imaging$of$rat$neurons$and$their$extracellular$matrix$

P16$ Dorin$Simionesie$ University$of$Strathclyde$ The$Asphaltene$Enigma,$Enhancing$crude$oil$recovery$

P17$ Yakun$Gao$ University$of$Oxford$ Nanostructures$on$the$SrTiO3(001)$Surface$

P18$ Aiyeshah$Alhodaib$ Lancaster$University$Photoluminescence,$photoresponse$and$leakage$current$in$site$controlled$InAsSb$nanowires$

P19$ Katarzyna$Krupski$ University$of$Warwick$Structural$optimization$of$titanium$dioxide$of$(4x1)$reconstruction$for$photocatalytic$applications$

P20$ TJ$Petty$ University$of$Liverpool$ The$dependence$of$tungsten$fuzz$growth$on$He$ion$fluence$

P21$Mohammed$Althobaiti$

University$Of$Liverpool$Band$Alignment$of$Ta2O5$on$Sulphur$Passivated$Germanium$by$XBray$Photoelectron$Spectroscopy$

P22$Abdullah$AlBMahboob$

University$of$Liverpool$Transition!state!limited!kinetics!in!stabilizing!intermetallic!surfaces$

P23$ Hem$Raj$Sharma$ University$of$Liverpool$Templated!quasicrystalline!films!of!single!elements!and!molecules$

!


List!of!Participants!

!!

Ruben$AhumadaBLazo$ University$of$Manchester$ Katarzyna$Krupski$ University$of$Warwick$Aiyeshah$Alhodaib$ Lancaster$University$ Aleksander$R.$Krupski$ University$of$Warwick$Mohammed$Althobaiti$

University$of$Liverpool$ James$Lawrence$ University$of$Warwick$

Kingsley$Amamchukwu$

Manchester$Metropolitan$University$

Dr$Ralph$Leech$ Edwards$Vacuum$

Peter$Beton$ University$of$Nottingham$ Evangelos$Liamas$ University$of$Strathclyde$Jonathan$Blohm$ University$of$Warwick$ Mike$Lowe$ University$of$Liverpool$Philip$Blowey$ University$of$Warwick$ Chris$McConville$ University$of$Warwick$Clare$Carson$ Lucideon$Ltd$ Ronan$McGrath$ University$of$Liverpool$Gareth$Chumbley$ University$of$Nottingham$ Philip$Moriarty$ University$of$Nottingham$

Sam$Coates$ University$of$Liverpool$Sebastiaan$Van$Nuffel$

University$of$Nottingham$

David$Connell$ University$of$Strathclyde$ James$O'Shea$ University$of$Nottingham$Giovanni$Costantini$ University$of$Warwick$ Luis$M.$A.$Perdigao$ University$of$Warwick$

Ovidiu$Crisan$National$Institute$for$Materials$Physics,$Bucharest,$Romania$

TJ$Petty$ University$of$Liverpool$

Vin$Dhanak$ University$of$Liverpool$ Rasmita$Raval$ University$of$Liverpool$Wendy$Flavell$ University$of$Manchester$ Benjamin$Robinson$ Lancaster$University$

Yakun$Gao$ University$of$Oxford$ David$Sawtell$Manchester$Metropolitan$University$

James$Gibbon$ University$of$Liverpool$ Antony$Scimone$Manchester$Metropolitan$University$

Joshua$S.$Gibson$ University$of$Nottingham$ Hem$Raj$Sharma$ University$of$Liverpool$Yvonne$Grunder$ University$of$Liverpool$ Dorin$Simionesie$ University$of$Strathclyde$Adrian$Hannah$ STFC$ Simon$Smalley$ UCLan$Mike$Hardy$ Queen's$University$Belfast$ Vibha$Srivastava$ Lancaster$University$Sanger$Hars$ University$of$Liverpool$ Karen$Syres$ UCLan$

Zoe$Henderson$ University$of$Liverpool$ Louise$Tetlow$Manchester$Metropolitan$University$

David$Hesp$ University$of$Liverpool$ Stuart$Thorn$ University$of$Liverpool$John$Hodgkinson$ University$of$Salford$ Reza$Valizadeh$ STFC$

Andrew$Hodgson$ University$of$Liverpool$Dr$Kathryn$Whitehead$

Manchester$Metropolitan$University$

Werner$Hofer$ Newcastle$University$ Thomas$Whittles$ University$of$Liverpool$Robert$Jones$ University$of$Nottingham,$$ Andrew$Williamson$ University$of$Manchester$James$Keen$ Lancaster$University$ Phil$Woodruff$ University$of$Warwick$Manoj$Kesaria$ Lancaster$University$

$ $!!


!

9:35!am!

Porphyrin!Assembly!at!Surfaces:!From!SubOMolecular!Imaging!to!

OnOSurface!Synthesis!of!Oligomers!'

Rasmita$Raval$

Surface'Science'Research'Centre'and'Department'of'Chemistry,'University'of'Liverpool,'L69'7ZD,'UK'

!Porphyrins!organised!at!surfaces!have!promising!applications!in!catalysis,!magnetic!memories,! solar! cells! and! optical! devices.! The! use! of! advanced! scanning! probe!imaging,! surface! spectroscopies! and! periodic! density! functional! theory! is! now!beginning!to!throw!light!on!how!these!complex!molecules!behave!in!2Ldimensional!systems.! This! talk! will! progress! from! subLmolecular! imaging! of! individual!porphyrins! at! surfaces! to! demonstrating! how! collections! of! porphyrins! can! show!remarkable! selfLorganising! abilities.! The! latter! leads! to! beautiful! nanoscale!architectures!and!organised!patterns![1,2],!driven!by!a!balance!of!strong!moleculeLsurface! bonding! and! weak! supramolecular! interactions,! that! lead! to! longLrange!chiral! assemblies! [1].! Advancing! from! supramolecular! assemblies! to! covalent!assemblies,!we!show!that!surface!reactivity!can! initiate!clean! 'onLsurface'!coupling!of! porphyrins! via! CLH! bond! activation.! This! allows! 2LD! synthesis! of! organic! and!organometallic!porphyrin!oligomers![2L7],!enabling!complex!polyLporphyrin!entities!to! be! realised! at! a! surface.! From! these! organised! molecular! units! arise! the!possibility! of! complex! functions! like! molecular! recognition,! sensing,! chirality,!nanomagnetism!and!defined!reaction!spaces!that!are!important!in!nanoscience.!![1]!! P.! Donovan,! A.! Robin,!M.! S.! Dyer,!M.! Persson,! R.! Raval,! ‘Unexpected!Deformations! Induced! by!

Surface! Interaction! and! Chiral! SelfLAssembly! of! Co(II)LTetraphenylporphyrin! adsorbed! on!Cu(110):!A!combined!STM!and!Periodic!DFT!study’.!Chemistry,!A!European!Journal,!16!(2010)!!11641.!

[2]!!! S.!Haq,!F.!Hank,!M.!S!Dyer,!M.!Persson!!P.!Iavicoli,!D.!B.!Amabilino!and!R.!Raval,!‘Clean!Coupling!of!Unfunctionalized!Porphyrins!at!Surfaces!To!Give!Highly!Oriented!Organometallic!Oligomers’,! J.!Am.!Chem.!Soc.!133!(2011)!12031!

[3]!!! M.!In’t!Veld,!P.!Iavicoli,!S.Haq,!!D.!B.!Amabilino!!and!R.!Raval,!“Unique!Intermolecular!Reaction!of!Simple!Porphyrins!at!a!Metal!Surface!gives!Covalent!Nanostructures”,!Chem.!Comm.,!2008,!1536!

[4]! F.! Hanke,! S,Haq,! R.Raval! and! M.Persson.! ‘Heat! to! connect:! Surface! commensurability! directs!covalent!oneLdimensional!selfLassembly’,!!ACS!Nano,!5!(2011)!9093.!!

[5]!! M.! Dyer.! A.Robin,! S.! Haq,! R.Raval,! M.Persson,! J.Klimes! ,! ‘Understanding! the! Interaction! to!Reactive!Metal!Substrates:!Structure,!Bonding!and!AdLatom!capture,!ACS!Nano,!!5!(2011)!1831.!!

[6]! ! ! S.! Haq,! F.! Hanke,! J.! Sharp,! M.! Persson,! D.! B.! Amabilino! and! R! Raval,! ‘Versatile! BottomLup!Construction! of! Diverse! Macromolecules! on! a! Surface! Observed! by! Scanning! Tunnelling!Microscopy’,!ACS!Nano,!8!(2014)!8856.!

[7]!! S!Haq,!B!Wit,!H!Sang,!A!Floris,!Y!Wang,!J!Wang,!L!PérezLGarcía,!L!Kantorovitch,!D!B.!Amabilino,!R!Raval,! ‘A! small!molecule!walks! along! a! surface! between! porphyrin! fences! assembled! in! situ’.!Angewandte!Chemie!Int!Ed.!2015,!DOI:!10.1002/anie.201502153!


!

!

!

!

10:10!am!

Surfaces!of!quasicrystals!and!related!complex!metallic!alloys!'

Ronan$McGrath$

University'of'Liverpool'!The!surfaces!of!quasicrystals!and!related!complex!metallic!alloys!are!of!fundamental!scientific!interest.!Following!a!general!introduction!to!the!field,!I!will!cover!their!use!as!templates!in!epitaxy!and!molecular!adsorption.!I!will!also!review!their!potential!application!as!catalytic!materials.!


!

!

11:15!am!

Quantitative!adsorbate!surface!structure!determination!'

Phil$Woodruff$

University'of'Warwick'!Studies!of!wellLcharacterised!single!crystal!surfaces!are! increasingly!dominated!by!realLspace! imaging! techniques,!most! notably! scanning! tunnelling!microscopy.! The!resulting! images! provide! atomicLscale! images,! and! while! there! is! sometimes!ambiguity!as!to!what!atoms!are!imaged!(are!adsorbed!atoms!on!the!surface!or!in!the!surface?),! and! how! they! are! imaged! (as! a! protrusion! or! a! dip),! such! images!commonly!allow! the! lateral! adsorption! site! to!be!determined! if! images! show!both!adsorbate!and!substrate!atoms.!However,!STM!is!intrinsically!a!probe!of!the!spatial!variation! of! valence! electronic! structure,! and! does! not! provide! quantitative!information! on! the! exact! location! of! the! atomic! centres! and!hence! on! interatomic!bondlengths.! True! quantitative! surface! structural! methods! address! this! problem,!but!are!significantly!less!direct!in!interpretation.!After!a!very!brief!broad!survey!of!available!methods! I! will! focus! on! two! specific!methods,! photoelectron! diffraction!(PhD)! and! normal! incidence! XLray! standing! waves! (NIXSW).! Both!methods! allow!local! adsorbate! structures! to! be! determined! in! an! elementLspecific! and! chemicalLstate! specific! fashion.! This!will! be! demonstrated!with! several! examples! of! atomic!and! molecular! adsorbate! system.! The! key! instrumental! requirements! for! both!methods!are!now!in!place!at!the!UK's!Diamond!synchrotron!radiation!source.!

!


!

!

11:50!am!

Electronic!Structure!and!Properties!of!Transparent!Conducting!

Oxide!Semiconductors!'

C.$F.$McConville$$

Department'of'Physics,'University'of'Warwick,'Coventry'CV4'7AL'UK'!Oxide!semiconductors!have!become!of!great!technological! interest!and!importance!in! recent! years! with! opportunities! to! improve! existing! materials! and! device!applications.!!This!is!particularly!true!for!a!subLgroup!of!materials!that!display!both!optical! transparency! and! high! electrical! conductivity,! soLcalled! transparent!conducting!oxides! (TCO's).! !The! fact! that!some!of! these!materials,! such! indium!tin!oxide! have! been! around! for! many! years! and! seen! significant! industrial! use! as!transparent!conductors!in!a!relatively!low!quality!form,!has!perhaps!contributed!to!the!belated!recognition!of!of!using!these!materials!as!semiconductors! in!their!own!right.! ! Here,! examples! of! the! surface! and! bulk! electronic! properties! of! epitaxially!grown!oxide!semiconductors!(In2O3,!CdO!and!ZnO)!will!be!discussed!along!with!the!effects! of! modifying! these! surfaces! by! controlled! adsorption.! The! valence! band!density! of! states! and! the! surface! electronic! properties! of! these! TCO's! have! been!studied! using! highLresolution! angleLresolved! photoemission! (ARPES),! while! coreLlevel! photoemission! spectroscopy! with! hard! xLrays! (HAXPES)! is! compared! with!theoretical! DFT! band! structure! calculations.! ! A! common! property! of! these! oxide!semiconductors! is! the! presence! of! an! electron! accumulation! layer! at! the! surface.!!While!this!is!similar!to!that!found!at!the!surfaces!of!materials!such!as!InN!and!InLrich!InGaN,! it! is! in!marked! contrast! to! the! electron!depletion! typically!observed!at! the!surfaces!of!conventional!IIILV!and!IILVI!semiconductor!materials.!!More!unusual!still!is! the! quantized! nature! of! this! surface! 2D! electron! gas.! ! The! origins! of! these!phenomena!will!be!discussed!in!terms!of!the!band!structure!and!intrinsic!properties!of!the!materials.!!


12:25!pm!

Pauli's!principle!in!dynamic!force!microscopy:!Do!we!really!see!

chemical!bonds?!

!

Philip$Moriarty$

University'of'Nottingham'!Exceptionally! clear! images! of! intramolecular! and! intermolecular! “bonds”! can! now!be!attained!in!dynamic!force!microscopy!(DFM)!through!the!combination!of!tip!apex!'engineering'! and! operation! in! what! has! become! known! as! the! Pauli! exclusion!regime!of!the!tipLsample!interaction![1L6].!As!is!always!the!case!for!any!microscopy!technique,! however,! the! images! represent! a! convolution! of! the! properties! of! the!imaging!system!and!the!object!under!investigation.!The!tip,!particularly!in!the!Pauli!exclusion! regime,! can! be! very! far! from! a! nonLinvasive! probe! of! the! molecular!system.!We!have!used!dynamic! force!microscopy!(DFM)! to!quantitatively!map! the!tipLsample! force! field! for! naphthalene! tetracarboxylic! diimide! (NTCDI)! molecules!hydrogenLbonded!in!twoLdimensional!assemblies![4].!A!comparison!of!experimental!images! and! force! spectra! with! their! simulated! counterparts! shows! that!intermolecular! contrast! arises! from! repulsive! tipLsample! interactions! whose!interpretation! can!be!aided!via! an!examination!of! charge!density!depletion!across!the! molecular! system.! Interpreting! DFM! images! of! hydrogenLbonded! systems!therefore! necessitates! detailed! consideration! of! the! coupled! tipLmolecule! system!(including! the! dynamics! and! relaxation! of! the! tip! [4L6]):! analyses! based! on!intermolecular!charge!density!in!the!absence!of!the!tip!fail!to!capture!the!essential!physical!chemistry!underpinning!the!imaging!mechanism.!More!broadly,!I!will!focus!on!the!key!question!of!whether!it!is!possible!to!make!the!claim!that!chemical!bonds!are!resolved!in!DFM!images.!Two!important!studies![5,!6]!have!very!recently!shown!that! features!which! could! be! interpreted! as! intermolecular! bonds! in! DFM! images!arise! instead! from! artefacts! due! to! probe! relaxation.! I!will! show! that! this! type! of!artefact! also,! surprisingly,! arises! in! a! purely! van! der!WaalsLinteracting! system! of!spherical!(rather!than!planar)!molecules:!a!2D!assembly!of!C60!molecules.!!![1]!! L!Gross,!F!Mohn,!N!Moll,!P!Liljeroth,!and!G!Meyer.!Science,!325!(2009)!1110!![2]!! Dimas!G.!de!Oteyza,!et!al.,!Science,!340!(2013)!1434!![3]!! Jun!Zhang,!Pengcheng!Chen,!Bingkai!Yuan,!Wei!Ji,!Zhihai!Cheng,!and!Xiaohui!Qiu,!Science!342!(2013)!611!![4]!! A! Sweetman,! SP! Jarvis,! H! Sang,! I! Lekkas,! P! Rahe,! Y! Wang,! J! Wang,! N!Champness,!L!Kantorovich,!and!P!Moriarty,!Nature!Communications!5!(2014)!3931!![5]!! P! Hapala,! G! Kichin,! CF!Wagner,! S! Tautz,! R! Temirov,! and! P! Jelinek,! Physics!Review!B!90!(2014)!085421!![6]!! Sampsa!K.!Hamalainen,!et!al.,!Phys.!Rev.!Lett.!113!(2014)!186102!


!

!

2:45!pm!

Molecular!adsorption!and!organisation!on!boron!nitride!and!

molybdenum!disulphide!'

Vladimir$V.$Korolkov,$Alex$Summerfield,$James$Kerfoot,$Simon$A.$Svatek,$Neil$Champness,$Lixu$Yang,$Nick$A.$Besley,$Takashi$Taniguchi,$Kenji$Watanbe$

Peter$H.$Beton$

University'of'Nottingham'!The!adsorption!of!a!range!of!molecules!on!layered!materials!has!been!investigated!using! using! high! resolution! atomic! force! microscopy! (AFM).! We! have! observed!several! arrangements! of! molecules! which! are! stabilized! by! hydrogen! bonding!including!a!bimolecular!layer!formed!by!perylene!tetracarboxylic!diLimide!(PTCDI)!and!melamine!which! form! an! open! nanoporous! array! in!which! the! planar! PTCDI!molecules! are! adsorbed! parallel! to! the! substrate! [1]! as! shown! in! Figure! 1.! The!networks!are!deposited!from!solution!by!immersion!of!BN!and!MoS2!substrates!and!the!ordering!may!be!improved!by!postLannealing!in!an!inert!atmosphere.!We!have!also!investigated!the!adsorption!of!5,10,15,20Ltetrakis(4Lcarboxylphenyl)porphyrin!(TCPP),! a! dye! molecule! with! a! planar! porphyrin! macrocycle! as! its! core.! This!molecule!forms!an!open!square!array,!also!stabilized!by!hydrogen!bonding!through!carboxlic!acid!pendant!groups!which!steer!the!arrangement!so!that!macrocycle!lies!parallel! to! the! surface.! In! this! arrangement! the! molecular! layer! is! strongly!fluorescent!showing!lines!which!are!redLshifted!from!solution.!When!molecules!are!adsorbed!on!MoS2!they!form!similar!structures!but!the!resulting!islands!are!smaller!and! less! ordered,! and,! due! to! the! smaller! band! gap! of! MoS2,! fluorescence! is!quenched.! We! also! present! density! functional! theory! calculations! of! the!conformation! of! adsorbed! molecules! and! numerical! estimates! of! the! hydrogen!bonding!and!adsorption!energies.!


!

!

!

3:20!pm!

Dynamic!processes!observed!by!scanning!tunnelling!

microscopes:!vibrations,!diffusions!and!reactions!'

Werner$A.$Hofer1,$J.$C.$Polanyi2$and$H.$J.$Gao3$

1'School'of'Chemistry,'Newcastle'University,'2'Department'of'Chemistry,'Toronto'University,'3'Institute'of'Physics,'Chinese'Academy'of'Sciences,'Beijing'

Dynamic! processes! in! scanning! tunnelling!microscopy! (STM)! are! increasingly! the!focus!of! cutting! edge! research!due! to! their! importance! for! energy! conversion! and!reaction!processes.! It! is! in! principle! possible! to! study! these! processes! by! suitable!adaptation!of!STM!theory!and!a!stepLbyLstep!analysis!of!the!processes!themselves.!I!shall!give!several!examples!where!such!a!detailed!understanding!is!indispensible!for!a!comprehensive!understanding!e.g.!in!atomic!switching!and!diffusion!processes,!in!molecular! growth! processes,! condensation! reactions,! and! long! range! molecular!propagation!even!on!reactive!surfaces.!!!WA!Hofer,!AS!Foster!and!AL!Shluger,!Theories!of!Scanning!probe!Microscopes!at!the!Atomic!Scale,!Reviews!of!Modern!Physics!75,!1287L1331!(2003)!PG!Piva!et!al.,!Field!regulation!of!singleLmolecule!conductivity!by!a!charged!surface!atom,!Nature!435,!658L661!(2005)!KR! Harikumar! et! al.,! DipoleLdirected! assembly! of! lines! of! 1,5Ldichloropentane! on!silicon!substrates!by!displacement!of!surface!charge,!Nature!Nanotechnology!3,!222L229!(2008)!KR!Harikumar!et! al.,! Cooperative!molecular!dynamics! in! surface! reactions,!Nature!Chemistry!1,!716L721!(2009)!KR!Harikumar!et!al.,!Directed!longLrange!molecular!migration!energized!by!surface!reaction,!Nature!Chemistry!3,!400L408!(2011)!L! Liu! et! al.,! Reversible! Spin!Control! of! Individual!Magnetic!Molecule! by!Hydrogen!Atom!Adsorption,!Scientific!Reports!3,!1210!(2013)!!!


!

!

3:55!pm!

Structural!Studies!of!Thin!Films!10O100s!Å thick!'

Robert$G$Jones$

Department'of'Physical'Chemistry,'University'of'Nottingham,'Nottingham,'NG7'2RD,'UK'!XLray!reflectivity,!where!the!reflected!intensity!is!measured!as!a!function!of!grazing!angle! of! incidence,! has! been! used! to! study! thin! films! (~10! Å! thick)! for! decades,!providing! electron! density! maps! of! both! buried! and! vacuum! interfaces.! Here! we!describe! our! initial! experiments! to! develop! the! structural! technique! of! variable!period! XLray! standing! wave! (VPXSW)! analysis,! which! consists! of! a! reflectivity!experiment!in!which!photoemission!from!the!surface!is!monitored!during!the!scan.!During!a!reflectivity!scan!an!XLray!standing!wave!is!formed!within!the!surface,!the!period! of! which! is! determined! by! the! XLray! angle! of! incidence.! By! analysing! the!intensity! of! the! photoelectron! peaks! as! successive! XLray! nodes/antinodes! sweep!through! the! positions! of! chemical! species! elemental! and! chemically! specific! (via!chemical!shifts)!structures!can!be!measured!along!the!surface!normal.!We!present!the!results!of!a!marker!layer!of!chloroform,!CHCl3,!(10±5!Å!thick),!adsorbed!on!top!of! a! layer! of! ionic! liquid,! 1LoctylL3Lmethylimidazolium! tetrafluoroborate,![C8C1Im][BF4],!(230±15!Å!thick)!deposited!at!90!K!onto!the!native!SiO2!layer!(30±5!Å)! on! a! silicon! surface.! A! fixed! photon! energy! of! 3000! eV! was! used! to! excite!photoelectrons!from:!Si!2p3/2,!2p1/2!(from!bulk!Si!and!oxide!shifted!Si),!C!and!N!1s!from!the!cation,!B!and!F!1s!from!the!anion,!Cl!1s!from!the!chloroform!and!O!1s!from!the! native! oxide! layer! and! from! background! H2O! adsorption! on! top! of! the!chloroform.!We!shall!also!present!some!preliminary!results!for!VPXSW!using!a!gold!substrate.!


!!

!

!

5:00!pm!

Unravelling!the!mysteries!of!solar!nanocells!O!surface!and!

interface!chemistry!in!quantum!dots!'

Wendy$Flavell$

The'University'of'Manchester'!There! is! an! urgent! requirement! to!make! better! use! of! the! 120,000! TW! of! power!provided!by!the!Sun,!by!using!it!to!generate!power,!or!by!using!its!energy!directly!to!make!useful!chemical! feedstocks.!At! the!University!of!Manchester,!we!are!working!to! develop! next! generation! solar! nanodevices,! that! could! be! used! for!microgeneration.! Core! components! of! our! prototype! devices! are! colloidal!semiconductor! quantum! dots! (QDs)! that! harvest! the! incident! light,! creating! an!electronLhole! pair! (exciton),! and! nLtype! and! pLtype! conductors! that! separate! the!charge.!Issues!of!key!importance!are!the!energy!level!lineLup!between!the!QDs!and!the!surrounding!components!of!the!cell,!and!the!influence!of!the!surface!properties!of!the!QD!on!charge!separation!into!the!device!and!carrier!multiplication!in!the!QD.!I!will!show!how!a!combination!of!synchrotron!radiation!and!laser!spectroscopies!may!be!used! to! investigate! the!surface!chemical! composition,! surface!ageing!and! ‘coreLshell’! structure! of! the! colloidal! QDs,! the! energy! levelLlineLup! and! the! charge!dynamics! in! photovoltaics.! I! will! also! illustrate! the! use! of! ultrafast! transient!absorption!spectroscopy!to!investigate!the!phenomenon!of!carrier!multiplication!in!QDs.!


!

5:35!pm!

Water!structures!and!the!wetting!of!metals!'

Andrew$Hodgson,$University$of$Liverpool$

University'of'Liverpool'!WaterLmetal! interfaces! are! important! in! fields! as! diverse! as! corrosion,!heterogeneous! catalysis! and! electrocatalysis,! but! models! for! the! waterLsolid!interaction! remain! relatively! crude,! and! often! little! is! known! about! the! species!present!at!the!surface!or!the!hydrogen!bonding!structures!formed.!Water!structures!are!delicate,!held!together!by!weak!waterLmetal!and!waterLwater!hydrogen!bonds,!and! small! changes! to! the! surface! can! introduce!dramatic! changes! to! the! structure!and!macroscopic!properties,!such!as!wetting.!!Key!issues!to!understand!include!how!water!wets!different!surfaces,!how!the!presence!of!hydroxyl!changes!the!first!layer!structure! and! how! the!molecular! structure! of! the! first!water! layer! influences! the!overall! properties! of! the! waterLsolid! interface.! This! talk! will! focus! on! how! the!hydrogen!bonding!structure!of!water!and!mixed!water/hydroxyl!layers!depends!on!the!symmetry!and!reactivity!of!some!simple!metal!surfaces,!particularly!how!water!adsorption! and! surface! wetting! is! modified! by! the! presence! of! hydroxyl! or! by!creation! of! a! 2D! nanoLstructured! surface,! for! example! an! ordered! surface! alloy.!Examples!will! include! the!wetting! of! Cu(110)! and! the! effect! of! the! surface! lattice!parameter! on! the! wetting! of! the! (√3x√3)R30°! Sn! M(111)! surface! alloys.! These!experiments! reveal! a! much! richer,! more! complex! picture! of! adsorption! than!originally!anticipated,!but!some!simple!general!considerations!persist!and!provide!new!models!for!the!structure!of!water!and!hydroxyl!at!metal!surfaces,!allowing!us!to!anticipate!and!rationalise!the!adsorption!behaviour!of!more!complex!surfaces.!


P01!SurfaceOfunctionalized!Cluster!Aggregated!Nanoparticles!'

O.$Crisan,$C.$Binns,$A.M.$Ellis,$K.$von$Haeften$

National'Institute'for'Materials'Physics,'Bucharest,'Romania'and'Department'of'Physics,'University'of'Leicester,'UK'

!A! novel! method! of! synthesis! of! clusterLassembled! magnetic! nanoparticles! is!presented! and! the!properties! of! the! obtained! gasLstabilised! surfaceLfunctionalized!Fe!oxide!clusters!are!reported.!A!home!made!UHV!chamber!connected!to!a!multiple!cluster! source,! is! presented.! The! technique! uses! Ar! gas! flow! which! captures!evaporated!metal!vapours!and!sputters!the!condensed!clusters!inLsitu!onto!suitable!chosen! substrates.! Extremely! rigorous! control! of! the! size! distribution! and! cluster!density! is! achieved.! Cluster! size! is! controlled! by! the! vapor! pressure! of! the!metal!source!inside!the!pickLup!chamber.!Detailed!analysis!of!the!TEM!micrographs!of!the!Fe! oxide! clusters! onto! C! coated! Cu! grids! shows! that! there! is! a! simple! linear!relationship!between!average!metal!cluster!size!and!metal!vapour!pressure!during!deposition.! Magnetic! properties! are! investigated! and! correlated! with! the! cluster!structure.! Enhanced! coercivity! is! observed! for! the! Fe! clusters! and! attributed! to!strong!planar!magnetic! anisotropy! induced!during! gas! exposure.! Initial! promising!results!towards!biomedical!applications!are!presented.!


P02!Adsorption!of!DBBA!and!coronene!on!Ag(100)!'

S.$Smalley$[1],$D.$Hesp$[2],$T.$Whittles$[2],$V.$R.$Dhanak$[2],$J.$A.$Smerdon$[1]$

[1]'UCLan'[2]'University'of'Liverpool'!Polymerisation! of! dibromobianthracene! (DBBA)! molecules! via! substrate! assisted!deLbromination! reactions! have! been! shown! as! a! viable!means! of! graphene! nanoLribbon! (GNR)! production! on! the! hexagonal! Ag(111)! and! Au(111)! substrates[1,2].!The!square!Ag(100)!surface!has!so!far!been!neglected!and!so!we!attempt!to!replicate!GNR! production! for! this! surface! to! determine! the! effects! the! square! surface!structure! has! on! GNR! formation.! Coronene! (Cn)! serves! effectively! as! graphene!nucleation!sites! for! smaller!organic!molecules[3].!Again,! little!work!has!addressed!the!effect!of!the!mismatched!symmetry!cubic!surfaces!present,!serving!as!motivation!for!our!study!of! the!Cn!/!Ag(100)!system.! ! In!separate!experiments,!DBBA!and!Cn!molecules!are!deposited!via!thermal!evaporation!on!a!Ag(100)!surface,!at!room!and!elevated! temperatures.! Molecular! adsorption! is! investigated! by! a! combination! of!low!energy!electron!diffraction!(LEED)!and!scanning!tunneling!microscopy!(STM)!.!STM!provides! sub!molecular! resolution! showing! that! islands!of!DBBA! form!below!monolayer! coverage,! and! align! predominantly! in! two! directions! perpendicular! to!one! another! as! dictated! by! the! symmetry! of! the! substrate.! Deposition! with! the!substrate! maintained! at! 400C! results! in! DBBA! polymerisation! and! subsequently,!formation!of!networked!GNRs.!Cn!coverage!at!monolayer!and!above!yields!a!highly!ordered! hexagonal! arrangement! producing! 12! point! LEED! patterns.! This! is!explained! via! the! 4! fold! symmetry! of! the! substrate! yielding! different! molecular!alignments! between! domains.! this! is! supported! by! STM! data! collected,! itself!comparable!to!results!obtained!for!Cn/Ag(111)[4,5].!!!![1]! J!Cai,!P!Ruffieux,!et!al.!"Atomically!precise!bottomLup!fabrication!of!graphene!nanoribbons",!Nature,!466:470,!2010!![2]! H!Huang,!D!Wei,!et!al.!"Spatially!resolved!electronic!structures!of!atomically!precise!armchair!graphene!nanoribbons"!Scientific!reports,!2:983,!2012!![3]! T! Wu,! G! Ding,! et! al.! "Continuous! graphene! films! synthesized! at! low!temperatures! by! introducing! coronene! as! nucleation! seeds",! Nanoscale,! 5:5456,!2013![4]! M!Lackinger,!S!Griessl,!et!al.!"Coronene!on!Ag(111)!investigated!by!LEED!and!STM!in!UHV",!Journal!of!Physical!Chemistry!B,!106:4482!2002!![5]! A! McKinnon,! M! Welland,! et! al.! "Observation! of! the! ordered! growth! of!coronene!on!Ag(111)!a!scanning!tunneling!microscopy!study!of!vacuum!deposited!molecules",!Thin!solid!films,!257:63,!1995!


P03!The!effects!of!Oxidation!on!the!Shell!Structure!of!Type!II!

Colloidal!Quantum!Dots!'

Andrew$Williamson$[1],$Atip$Pengpad$[1],$Hanna$Radkte$[1],$Simon$M.$Fairclough$[2],$Robert$C.$Page$[3],$Christopher$A.$Muryn$[3],$Karina$Schulte$[4],$Jacek$Osiecki$

[4],$David$J.$Binks$[1]$and$Wendy$R.$Flavell$[1].$$$

[1]$School$of$Physics$and$Astronomy$and$the$Photon$Science$Institute,$The$University$of$Manchester,$Manchester$M13$9PL,$United$Kingdom$[2]$School$of$Physics,$King's$College$London,$Strand,$London$WC2R$2LS,$United$Kingdom$[3]$School$of$Chemistry,$University$of$Manchester,$Oxford$Road,$Manchester$M13$9PL,$United$Kingdom$[4]$Lund$Universitet,$MAXBlab,$Ole$Römers$väg$1,$223$63,$

Lund,$Sweden$!Type!II!colloidal!semiconductor!quantum!dots!(QDs)!are!nanoparticles!with!a!!'coreLshell'! structure! which! on! photoexcitation! results! in! spatially! separated! carriers.!!This!structure!reduces!the!recombination!rate!for!these!carriers,!which!can!be!used!in!many!applications!such!as!solar!cells.!However,!colloidal!QDs!do!not!necessarily!have! the! target! composition,! or! have! complete! and! atomicallyLabrupt! interfaces!between! the! core! and! the! shell.! Moreover,! significant! surface! degradation! of!colloidal! QDs! has! been! observed[1],! and! this! influences! carrier! recombination! as!well! as! the! bandgap! structure! within! the! QDs.! Here,! we! have! used! synchrotronLexcited!depthLprofiling!XPS!to!investigate!how!oxidation!affects!the!structure!of!type!II!quantum!dots!at!the!interface!between!the!core!and!shell,!and!at!the!surface.! !In!this! work,! we! performed! depthLprofiling! XPS! on! CdTe! (core)/CdSe!(shell)/butylamine! (ligand)! QDs! and! used! a! fixed! energy! source! to! study! CdTe!(core)/CdSe! (shell)/3Lmercaptopropionic! acid,! (ligand)!QDs.! ! ! The! results! confirm!that! selenium! is! present! at! the! surface! of! the! QDs! as!we! expect! for! a! CdSe! shell.!However,!tellurium!is!found!throughout!the!QDs!which!suggests!the!alloying!of!the!core!and!the!shell.!Tellurium!oxide!is!observed!after!the!sample!was!aged!in!air.!This!implies!that!there!must!be!a!degree!of!coreLshell!alloying!occurring!in!synthesis,!as!confirmed!through!depthLprofiling.!Furthermore,!oxygen! is!able! to!diffuse! through!defects! in! the! nanocrystal! lattice! caused! by! lattice! mismatch! at! the! coreLshell!interface!oxidising!tellurium!found!in!the!QD!core.!!!!![1]! S.! J.! O.!Hardman,!D.!M.! Graham,! S.! K.! Stubbs,! B.! F.! Spencer,! E.! A.! Seddon,!H.! T.!Fung,! S.! Gardonio,! F.! Sirotti,!M.! G.! Silly,! J.! Akhtar,! P.! O’Brien,!D.! J.! Binks! and!W.!R.!Flavell,!Phys.!Chem.!Chem.!Phys,!2011,!13,!20275L83.!!!![2]!S.!M.!Fairclough,!E.!J.!Tyrrell,!D.!M.!Graham!et!al,!J.!Phys.!Chem.!C,!2012,!116!(51),!pp!26898–907.!


P04!SubOMicrosecond!Pulsed!Plasma!Surface!Modification!as!a!

Combinational,!all!Atmospheric!Pressure!Approach!to!NanoO

structured!Thin!Film!Production!'

J.L.$Hodgkinson,$H.M.$Yates,$D.W.$Sheel,$University$of$Salford$

University'of'Salford'!Atmospheric!pressure!(AP)!CVD!systems!have!significant!advantages!over!vacuum!based! processes! for! large! area,! low! cost! substrates! such! as! glass.! The! ability! to!control! the! surfaces! texture! is! also! of! considerable! advantage! for!many! thin! film!structures! .! The! nanoLscale! features! may! be! further! optimised! via! post! growth!etching,! by,! for! example,! to! round! from! sharp! vertices! or! induce! or! exaggerate!texture!in!a!film!material!that!is!intrinsically!smooth.!This!is!normally!achieved!via!low!pressure!plasma!treatments!or!wet!chemical!processes,!hence!the!presented!AP!plasma!approach!offers!reduced!capital!costs!combined!with!ease!of!scalability!and!process.!


!!

P05!Development!of!electrospray!source!for!deposition!of!large!

molecules!for!STM!studies!'

Luis$M.A.$Perdigao,$Jonathan$Blohm,$Daniel$Warr,$Alex$Colburn,$Mark$Barrow,$Giovanni$Costantini$$

Department'of'Chemistry,'University'of'Warwick'!In! this! poster,! the! development! of! a! novel! type! of!molecular! deposition! system! is!presented.! Our! project! aims! at! transferring! large! and! thermally! labile! functional!molecules!intact!into!the!gas!phase!and!to!softLland!them!onto!atomically!clean!and!flat!surfaces!with!the!final!goal!of!making!them!accessible!to!high!resolution!surface!analytical! techniques! such! as! scanning! tunnelling! microscopy! (STM)! and! XLray!photoemission! spectroscopy! (XPS).! A! particular! focus! will! be! on! studying! the!interaction!of!peptides!with!surfaces!and!on!determining!how!this! influences!their!assembly!and!conformation!‚!!including!the!effects!on!their!secondary!structure!‚!!by!means!of!STM.!Molecules!will!be!delivered!from!solution!in!atmospheric!conditions!to! a! sample! surface! located! in! ultraLhigh! vacuum! (UHV).! This!will! be! achieved!by!electrospray! ionisation,! followed!by!several! ion!optic!elements! that!will!guide!and!massLselect! ions! through! successive! differential! pumping! chambers! with! high!transmission.! Ion! optics! calculations! were! performed! using! the! SIMION! software!package.!A!new!design!of!an!ion!funnel!will!be!shown!whereby!the!electrodes!plates!have!variable!distance!between!them.!Multipolar!ion!guides!have!been!identified!as!an! effective! way! to! transfer! ions! through! the! differential! pumping! stages! with!minimal! losses.! Our! system! shares! some! design! characteristics! with! instruments!previously! reported! in! literature! [1L5],! but! combines! the! advantage! of! massLselection!and! low!temperature!STM!imaging,!which!will!prove!vital! for!these! large!molecule!imaging!studies.!!![1]!Gunaratne,!K.!D.!D.!et!al.,!Analyst!140,!2957‚!2963!(2015).!![2]!Hamann,!C.!et!al.!Rev.!Sci.!Instrum.,!82,!033903!(2011).!![3]!Rauschenbach,!S.!et!al.,!ACS!Nano!3,!2901‚!2910!(2009).!![4]!Satterley,!C.!J.!et!al.,!Nanotechnology!18,!455304!(2007).!![5]!Hadjar,!O.!et!al.,!Anal.!Chem.,!79,!6566‚!6574!(2007)!


P06!Investigation!of!Ionic!Liquids!for!stabilising!Sulphur!Dioxide!

on!!Cu(111)!surface!using!XOray!and!UltraOViolet!photoelectron!

spectroscopy!'

Gareth$Chumbley,$Joshua$Heaps,$Karen$Syres$and$Robert$G.$Jones.$$

Department'of'Physical'Chemistry,'School'of'Chemistry,'University'of'Nottingham,'Nottingham'NG7'2RD,'UK.'

!Ionic! liquids!are!potential!capture!agents! for!environmentally!sensitive!gases!such!as! SO2.! Temperature! programmed! desorption! studies! of! SO2! with! 1LoctylL3Lmethylimidazolium!tetrafluoroborate!([C8C1Im][BF4])!have!already!shown!that!SO2!is! highly! stabilised! by! this! ionic! liquid.! Here! we! use! XLray! and! ultraviolet!photoelectron!spectroscopy!to!study!the!coLadsorption!of!SO2!with![C8C1Im][BF4]!to! evaluate! the! causes! of! this! stability.! The! ionic! liquid!was! deposited! by! vapour!deposition,!at!a!rate!of!0.6! layers!per!minute,! simultaneously!with!SO2!adsorption!from!the!gas!phase,!at!2x10L7mbar,!at!103K!onto!Cu(111)!to!form!an!intimate!SO2LIL!"snow"!mixture!consisting!of!ion!pairs!and!the!SO2!.!Layered!experiments!were!also!carried! out! by! depositing! by! SO2! on! top! of! IL! "snow"! deposited! at! 103K,! and! on!compact!IL!glass!(formed!at!300K!and!then!cooled).!The!behaviour!during!thermal!annealing!was! observed.!Multilayer! pure! SO2!was! found! to! desorb! by! 123K!while!SO2! from!the!coLadsorbed!"snow”!was!stabilised!up!to!173K.!Layered!experiments!showed! that! a! considerable! amount! of! SO2! moved! into! the! IL! "snow"! and! was!stabilised! up! to! 153K,! while! a! small! amount! SO2! on! the! glass! layer! of! IL,! was!stabilised!up!to!143K.!


P07!Stabilisation!of!CO2!within!the!Ionic!Liquid![C8C1Im][BF4]!'

Joshua$S.$Gibson,$Robert$G.$Jones$

Department'of'Physical'Chemistry,'School'of'Chemistry,'University'of'Nottingham,'Nottingham,'UK'NG7'2RD'

!Ionic!Liquids! (ILs)!have!drawn!a!great!deal!of! attention!as! carbon!capture!agents,!and! in!order! to!understand! them!studies!must!be!performed!probing! the!CO2! ‚! ! IL!interaction.!Temperature!Programmed!Desorption!(TPD)!has!been!used!to!study!the!effects! of! the! Ionic! Liquid! 1LoctylL3Lmethylimidazolium! tetrafluoroborate!([C8C1Im][BF4])! on! the! stability! of! carbon! dioxide.! Experiments!were! performed!utilising!Line!of!Sight!Mass!Spectrometry!(LOSMS)![1].!IL!was!deposited!by!physical!vapour!deposition!at!a! rate!of!~1! layer!per!minute!while!CO2!was! leaked! into! the!chamber!between!5x10L8!and!1x10L6! !mbar.!This!study!shows!CO2!does!not! form!a!monolayer!on!a!gold!surface!at!~93!K,!with!no!TPD!peak!seen!for!those!experiments.!When!IL!and!CO2!are!dosed!at!the!same!time!the!IL!is!seen!to!stabilise!the!CO2!up!to!a! temperature! of! ~160! K! (minimum! stabilisation! of! Edes! ~17! kJmolL1).!Experimental! TPD! curves! have! been! compared! to! simulated! TPD! profiles,! using!hypothetical! CO2! states! with! a! range! of! binding! energies,! showing! that! there! are!many! different! CO2! environments! within! the! IL! with! activation! energies! of!desorption!between!26!‚!!43!kJmolL1.!!![1]!A.S.Y.!Chan,!M.P.!Skegg,!and!R.G.! Jones,! J.!Vac.!Sci.!Technol.!A,!19,!(2001),!2007L2012!


P08!Seeing!Beyond!the!Image:!Peptide!Mass!Spectrometry!and!

STM!'

Jonathan$Blohm,$Daniel$Warr,$Ben$Moreton,$Dr$Luis$Perdigao$and$Dr$Giovanni$Costantini$

University'of'Warwick'!Peptides! represent! a! class! of!molecules!with! high! potential! as!molecular! building!blocks! due! to! their! ready! availability,! wideLranging! functionalities,! intrinsic!biocompatibility,! and! chiral! properties! (except! glycine).! Our! interest! lies! in!supramolecular!selfLassembly!on!a!surface,!a!growing!field!with!many!possibilities!for!the!generation!of! functional! thin! films.!The!properties!of!peptides!seem!ideally!suited!for!such!an!application,! in!particular!their!availability!and!flexibility,!as!well!as!having!moieties!that!can!facilitate!supramolecular!selfLassembly,!as!evidenced!in!nature.! To! study! the! selfLassembly,! ultraLhigh! vacuum! (UHV)! scanning! tunnelling!microscopy!(STM)!is!an!ideal!tool!given!its!high!resolution!capabilities.!A!relatively!small! amount! of! peptide! STM! data! exists! however,! and! the! overall! picture! is! still!unclear! as! to! the! applications! of! such! molecules.! Part! of! the! lack! of! data! can! be!attributed!to!a!bottleneck!that!exists!in!depositing!the!peptides!on!a!surface!in!UHV.!Typically,! the! peptides! are! deposited! on! the! relevant! surface! via!molecular! beam!epitaxy!(MBE).!High!temperature!MBE!can!result!in!the!thermal!decomposition!of!a!sample,!with!larger!molecules!and!those!with!weaker!bonds!more!likely!to!fragment.!A! question! naturally! arises! as! to! where! the! limit! of! sublimation! lies,! and! in! the!context!of!peptides,!what! is! the! longest! and/or!most! complex!peptide! that! can!be!sublimed!intact.!In!order!to!address!this!issue,!we!have!studied!a!series!of!peptides!of! varying! length! and! functionality! and! ascertained! whether! they! survive!sublimation,!by!means!of!electrospray! ionisation!mass!spectrometry! (ESILMS).!We!also! present! some! preliminary! STM! results! for! a! peptide! that! shows! particularly!interesting! behaviour:! diLphenylalanine! (PheLPhe),! and! in! doing! so! display! that!sometimes!one!needs!to!delve!beyond!the!STM!image!in!order!to! fully!understand!the!selfLassembly!process,!even!when! the!results!may! initially!seem!simple.! In! the!longer!term,!we!are!developing!a!new!STM!system!that!will!adapt!the!electrospray!technique! from! mass! spectrometry! as! a! ‘soft’! deposition! technique,! so! as! to!circumvent! the! thermal! sublimation! process! entirely! and! access! new! possibilities!for!selfLassembly.!


P09!UHV!compatible!electrospray!deposition!for!the!deposition!

of!complex,!fragile!and!nonOvolatile!molecules!on!surfaces!'

James$O'Shea,$Rob$Temperton,$Mike$Smith$and$many$others$$

School'of'Physics'&'Astronomy,'University'of'Nottingham'!The!deposition!of!molecules!on!surfaces!under!UHV!conditions!has!provided!us!with!incredible!insight!into!the!chemical,!electronic!and!geometric!structure!of!moleculeLsurface! interactions! using! techniques! ranging! from! electron! spectroscopy! to!scanning!probe!microscopy.!Gaseous!molecules!are!easily!deposited!in!vacuum!and!larger!molecules!can!be!deposited!by!thermal!evaporation!of!sublimation.!But!there!comes! a! point!where! the!molecule! is! so! large! or! fragile! that! it! has! no! significant!vapour! pressure! below! its! decomposition! temperature.! Clearly! the! library! of!molecules! that! fall! into! this! category! is! vast! and! includes! polymers,! many!organometallic! complexes,! proteins! and! nanoparticle! clusters.! Using! electrospray!ionization! we! can! take! large,! fragile! and! nonLvolatile! molecules! directly! from!solution!into!the!gasLphase!and!capture!the!resulting!beam!into!a!vacuum!system!to!be! skimmed,! cleaned! and! even! massLselected! before! impinging! on! an! atomically!clean! surface! in!UHV.! Electrospray! deposition! in! vacuum!has! enabled! us! to! apply!surface! science! techniques! to! study! dye! molecules,! macromolecules,! nanorings,!single!molecule!magnets!and!proteins!on!surfaces,!and!to!begin!building!functional!surfaces!and!devices!with!complex!molecules.!


P10!STM!Study!of!2D!SelfOAssembled!KetoneObased!MetalO

Organic!Structures!'

J.$Lawrence(1),$A.$Della$Pia(1),$M.$Riello(2),$D.$Stassen(3),$D.$Bonifazi(3),$A.$De$Vita(2)$and$G.$Costantini(1)$$

[1]'Department'of'Chemistry,'University'of'Warwick,'CV4'7AL,'UK'[2]'Department'of'Physics,'King’s'College'London,'WC2R'2LS,'UK'[3]'Department'of'Chemistry,'Université'de'

Namur,'B[5000'Namur,'Belgium'!An! investigation! into! the!usage!of! the!ketone! functional!group! in! the! formation!of!novel!2D!metalLorganic!structures!was!performed,!as!part!of!an!effort!to!expand!the!‘toolbox’! of! supramolecular! surface! science.! The! selfLassembly! of! pyreneL4,5,9,10Ltetraone!(PTO)!on!Cu(111)!was!examined!via!scanning!tunnelling!microscopy!(STM)!due! to! its! potential! binding! ability! with! metal! surface! atoms.! MetalLorganic!structures!were!indeed!observed!on!the!surface,!formed!through!the!linkage!of!the!PTO!ketone!groups! to! copper!adatoms.!The! coLdeposition!of!PTO!with! iron!atoms!produced! new! filamentLstructured! metalLorganic! complexes.! Crucially,! the! iron!deposition!rate!was!found!to!affect!the!resulting!surface!assembly.!!


P11!Growth!of!Pb!on!the!Threefold!Surface!of!a!AgOInOYb!

Quasicrystal!'

S.Thorn,$S.Hars,$M.Lowe,$R.McGrath,$H.R.Sharma$$

Department'of'Physics,'Surface'Science'Research'Centre,'University'of'Liverpool,'UK'!Since! the! availability! of! single! grain! quasicrystals! (QCs),!much! research! has! been!done!on!deposition!of!elements/molecules!onto!these!surfaces![1].!This!research!has!predominantly! been! related! to! how! the! adsorbates! will! arrange! themselves!according!to!the!structure!onto!which!they!are!being!adsorbed,!observed!using!STM.!The!QC!AgLInLYb!is!one!such!sample!in!which!recent!work!of!this!manner!has!been!carried! out! [2L5],! whereas! previous! work! has! been! with! AlLbased! QCs.! It! is!considered! that! icosahedral! (iL)! AgLInLYb! is! comprised! of! TsaiLtype! clusters! [6].!These! clusters! are! interlocking! shells! of! the! constituent! elements,! ending! in! a!rhombic!triacontahedral!(RTH)!cluster.!Due!to!the!minimisation!of!surface!energies!the! AgLInLYb! QC! is! preferentially! cut! through! the! cluster! centre.! This! provides!particular! ‘motifs’! to! be! presented! at! the! surface.! It! is! at! these! motifs! in! which!adsorbates!are!observed!to!preferentially!adsorb.!A!continuation!of!this!observation!leads!to!the!hypothesis!that!any!successive!deposited!elements!will!act!to!recreate!the!clusters!that!have!been!terminated.!This!has!been!recently!shown!on!iLAgLInLYb!in! a! display! of! a! single! element! 3Ldimensional! Pb!QC! (whereas! previous! research!demonstrates!2D!thin!films)![7].!The!research!carried!out!was!on!the!5Lfold!surface!in! order! to! reconstitute! this! structure! as! single! element.! In! order! to! more!comprehensively!complete!the!research,!the!same!is!attempted!on!the!3Lfold!surface!of!the!same!iLAgLInLYb!QC.!Data!so!far!suggests!that!the!Pb!adsorbs!according!to!the!3Lfold!symmetry!of!the!substrate.!Further!deposition!leads!to!growth!of!tetragonal!Pb!islands!with!approximately!1!nm!base!edges!in!preference!to!completion!of!the!previous!monolayer.!!!1.! P.!J.!Nugent!et!al.,!Philosophical!Magazine,!91:19L21,!(2011)!2862L2869!!2.! Sharma!et!al.,!Phys.!Rev.!B,!80,!(2009),!121401!!3.! Cui!et!al.,!J.!Phys.:!Condens.!Matter,!24,!(2012),!445011!!4.!! Cui!et!al.,!J.!Phys.:!Condens.!Matter,!26,!(2014)!015001!!5.!! Cui!et!al.,!Acta!Physica!Polonica!A,!126,!(2014),!2!!6.!! Tsai!et!al.,!Nature,!408,!(2000),!6812!!7.!! Sharma!et!al.,!Nature!Communications,!4,!(2013),!2715!!!


P12!Consideration!of!the!Coffee!Ring!Enhancement!Factor!for!

More!Comparable!Surface!Enhanced!Raman!Scattering!(SERS)!

Measurements!'

Mike$Hardy,$Ryan$McCarron,$and$Paul$Dawson$

Centre$for$Nanostructured$Media,$School$of$Mathematics$and$Physics,$Queen’s$University$Belfast,$BT7$1NN,$Belfast,$United$Kingdom.$

!Surface! enhanced! Raman! scattering! /! spectroscopy! (SERS)! has! struggled! to!establish! itself! as! an! analytical! technique,!most! notably! due! the! inhomogeneity! of!SERS! substrates.! Such! random! surface! asperities! render! reproducibility! of! the!Raman! signal! across! substrate! batches! poor;! this! is! currently! the! focus! of! much!SERS! research1.! In! addition,! there! has! been! an! inability! to!meaningfully! compare!SERS! substrates! in! the! literature! where! even! similar! SERS! substrates! often! have!wildly! different! enhancement! factors! (EFs).! Le! Ru! et! al.! (2007)! have! contributed!heavily! to! the! rigorous! definition! of! SERS! EFs! in! an! attempt! to! standardise!calculations2.! However,! we! contend! that! a! more! insidious! crop! of! experimental!SERS!issues,!often!voiced!cursorily!or!not!at!all! in!the!literature,!also!contribute!to!EF!discrepancies!among!similar!SERS!substrates.!One!such!effect! is! the!coffeeLring!phenomenon,! while! widely! discussed! and! well! understood3,! its! effect! on! EFs! in!SERS! is! seemingly! illLconsidered.! In! this! study,!we! consider! inhomogeneity! of! the!deposited! analyte!molecules! post! dropLcasting! and! evaporation!due! to! the! coffeeLring!effect!under!varying!conditions,!how!this!affects!subsequent!SERS!spectra,!and!EF!calculations.!We!explore!the!relevance!of!such!a!consideration!for!the!detection!of! parts! per! billion! concentration! nitric! and! sulphuric! acids! when! reacted! with!ammonium! hydroxide! to! form! a! solid! derivative! of! ammonium! salt! on! a! SERS!surface4.! The! motivation! here! is! trace! explosive! precursor! identification,! but! the!applicability!is!potentially!much!broader.!!!1! Hardy,!M.;!McCarron,!R.;!Doherty,!M.!D.;!Holsgrove,!K.!M.;!Mulholland,!P.!P.;!Dawson,! P.;! Winfield,! R.! J.! (2015)! Unpublished! poster:! Faraday! Discussion! 178!Nanoplasmonics,!16/02/15,!London,!UK.!!2! Le!Ru,!E.!C.;!Blackie,!E.;!Meyer,!M.;!Etchegoin,!P.!G.(2007)!J.!Phys.!Chem.!C.!111!(37).!!3! Deegan,!R.!D.;!Bakajin,!O.;!Dupont,!T.!F.;!Huber,!G.;!Nagel,!S.!R.;!Witten,!T.!A.!(1997)!Nature.!389.!!4! Hardy,!M.;!Doherty,!M.!D.;!Krstev,!I.;!Maier,!K.;!Möller,!T.;!Müller,!G.;!Dawson,!P.!(2014)!Anal.!Chem.!86!(18).!


P13!The!effect!of!surface!chemistry!on!protein!adsorption.!'

Evangelos$Liamas,$Paul$Mulheran,$Richard$Black,$Zhenyu$Zhang$

University'of'Strathclyde'!One! of! the!most! important! aspects! for! biomaterial! design! is! the! interaction! with!living! tissue,! which! can! cause! a! foreign! body! reaction! and! ultimately! implant!rejection.! Proteins!play! a! key! role! in! this! process!because! they! can! adsorb!on! the!biomaterial! surface! and! act! as! anchors! for! subsequent! cell! binding.! A!main! factor!that! govern! protein! adsorption,! and! thus! cell! binding,! is! the! chemistry! of! the!biomaterial! surface.In! this!project!we!use!a! fibronectin! fragment! to! investigate! its!adsorption!on!a!variety!of!surfaces.!The!fragment!consists!of!the!modules!8!to!10!of!the!type!III! fibronectin!(8L10FNIII)!and!contains!the!cellLbinding!and!synergy!sites!that!mediate!the!proteinLcell!interaction!through!integrins!on!the!surface!of!the!cell.!The!surfaces!that!have!been!used,! in!order!to!cover!a!range!of!different!properties!regarding! their! charge! and! hydrophilicity,! include! silica! and! selfLassembled!monolayers.!Besides!experimental!techniques,!Molecular!Dynamics!simulations!will!be! performed! using! NAMD! code! on! a! supercomputer! that! will! allow! us! to! use!explicit!solvent!model!for!a!more!realistic!representation.!The!combination!of!both!computational! and! experimental! techniques! and! the! way! they! complement! and!guide!each!other!during!this!project,!aim!to!provide!us!with!a!better!understanding!of! the!protein!adsorption!process.At!a! later! stage,!CoarseLGrained!simulations!will!be!used! in! order! to! develop! a! predictive!model! for! the!movement! of! the!proteins!onto!the!surfaces.!


P14!Physicochemical!Characterisation!and!Analysis!of!Peptide!

Adsorption!Onto!Inorganic!Surfaces!for!Use!in!Immunotherapies!'

D.$Connell$[1],$P.$Mulheran$[1],$V.$Ferro$[2],$B.$Jachimska$[3]$

[1]'Chemical'and'Process'Engineering,'University'of'Strathclyde'[2]'Strathclyde'Institute'of'Pharmacy'and'Biomedical'Sciences,'University'of'Strathclyde'[3]'Jerzy'Haber'Institute'

of'Catalysis'and'Surface'Chemistry,'Krakow,'Poland'!The!field!of!nanomedicine!is!becoming!increasingly!important!in!the!pharmaceutical!industry.! As! such! the! synthesis! and! characterisation! of! inorganic! nanoparticles! is!necessary! in! the! development! of! novel! drug! delivery! and! therapy! systems.! It! is!proposed! that! an! inorganic! nanoparticle! can! act! as! a! foreign! carrier! particle! for!adsorbed!peptides,!thus!stimulating!an!immune!response!against!these!peptides!in!vivo.!Consequently!novel!vaccines!can!be!developed!against!these!peptides,!to!pave!the! way! for! immunotherapies! against! conditions! in! which! the! adsorbed! peptide!plays!a!major!part.This!work!focusses!on!the!characterisation!of!silica!nanoparticles!and! their! interaction!with! peptides! for! optimal! presentation! of! the! peptide! to! the!immune! system! for! antibody! production.! The! interactions! at! this! step! allow! the!optimum!design!of! the!nanoparticle!with!surface!peptides! that!are! free! to! interact!with!the!surrounding!environment,!thus!having!the!potential!to!invoke!a!biological!response.!Dynamic! light! scattering!and!zeta!potential!measurements!were!used! to!investigate! the! properties! of! silica! nanoparticles! in! electrolyte! solutions.! This!provided!information!on!the!behaviour!of!these!nanoparticles! in!solution!and!thus!insight!as!to!how!they!may!behave!in!vivo.!Quartz!crystal!microbalance!and!surface!plasmon! resonance! measurements! were! also! used! in! order! to! investigate! the!adsorption!of!the!peptides!onto!a!silica!surface.!Through!running!these!experiments!at! various! pH! levels! and! ionic! strengths! the! optimum! conditions! for! peptide!coverage!of!silica!nanoparticles!could!be!determined,!enabling!enhanced!design!of!silica! nanoparticleLpeptide! system! and! thus! providing! invaluable! data! to! inform!immunisation!studies.!


P15!3D!TOFOSIMS!imaging!of!rat!neurons!and!their!extracellular!

matrix!'

Sebastiaan$Van$Nuffel[1,2],$Noah$Russell[2]$and$Mischa$Zelzer[1,3]$$

[1]'University'of'Nottingham,'School'of'Pharmacy,'Boots'Science'Building,'University'Park,'Nottingham,'NG7'2RD,'UK'[2]'University'of'Nottingham,'Neurophotonics'Lab,'Faculty'of'Engineering,'Nottingham,'NG7'2RD,'UK'[3]'National'Physical'Laboratory,'

Teddington,'Middlesex,'TW11'0LW'!TimeLofLflight! secondary! ion!mass! spectrometry! (TOFLSIMS)!has!proven! its! ability!to! characterise! surfaces! and! coatings! of! (in)organic!materials,! and! is! increasingly!used! for! biological! applications.! [1]! Combining! imaging! and! molecular! depth!profiling!it!is!possible!to!render!3D!chemical!images,!which!provides!a!novel!way!to!investigate! single! cells.! [2]! Major! challenges! lie,! however,! in! the! development! of!protocols! and! data! analysis! tools.! [3]! In! this! research,! photolithography! and! selfLassembled!monolayer!(SAM)!chemistry!are!used!to!create!substrates!with!cytophilic!and! Lphobic! areas! for! controlled! cell! adhesion! to! specific! areas.! This! facilitates!optical! microscopy,! interferometry! and! TOFLSIMS! measurements! at! the! same!position! making! crossLvalidation! between! the! different! techniques! possible.! The!surfaces! are! plated! with! either! primary! dissociated! rat! hippocampal! neurons! or!cortical!neurons.!The!cell!preparation!for!TOFLSIMS!consists!of!cryofixation!followed!by! freezeLdrying! in! an! effort! to! establish! a! protocol! that! preserves! the! cell!morphology.! Using! Matlab,! 3D! SIMS! images! are! quantitatively! compared! to!microscopy! images! to! validate! the! cell! positions! and! zLscaled! using! the!topographical! information! from! the! interferometry! measurements.! Multivariate!analysis! (MVA)!methods!such!as!principal!component!analysis! (PCA)!and!kLmeans!clustering!are!used!to!separate!cells,!extraLcellular!matrix!and!substrate!from!each!other! and! to! investigate! interL! as! well! as! intracellular! differences! in! order! to!distinguish!cell! types!and!cell!structures.!This!work!shows!that!MVA!is!a!powerful!tool! for!processing!3D!SIMS! image!data!of! single! cells! and! considerably! simplifies!the! data! analysis,! making! TOFLSIMS! far! more! accessible! for! research! involving!complex!biological!systems.!Keywords:!photolithography,!selfLassembled!monolayer!(SAM),! neuronal! cells,! freezeLdry,! timeLofLflight! (TOF),! secondary! ion! mass!spectrometry!(SIMS),!3D!chemical!imaging,!multivariate!analysis.!![1]!! Brunelle,! Alain,! David! Touboul,! and! Olivier! Laprévote.! Journal! of! Mass!Spectrometry!40.8!(2005):!985L999.!![2]!! Fletcher,!John!S.,!et!al.!Analytical!Chemistry!79.6!(2007):!2199L2206.!![3]!! Walker,!Amy!V.!Analytical!chemistry!80.23!(2008):!8865L8870.!


P16!The!Asphaltene!Enigma,!Enhancing!crude!oil!recovery!'

Dorin$Simionesie,$Dr$Z.J.$Zhang,$Prof.$J.$Sefcik,$Dr$P.$Mulheran$

Department'of'Chemical'and'Process'Engineering,'University'of'Strathclyde'Room'4.03G,'James'Weir'Building,'75'Montrose'Street'Glasgow'G1'1XJ'

!The!lack!of!understanding!of!the!basic!molecular!mechanisms!of!asphaltenes,!one!of!the!heavy! and!most! complex! components! of! crudeLoils,! cause! industrial! problems!such!as!reservoir!impairment,!inefficient!separation!of!water!from!oil,!obstruction!of!pipelines!and!extraction!pumps.!However,!controversy!still!shrouds!the!behavioural!patterns!of!the!asphaltenes!aggregation!mechanism!and!with!this!lack!of!knowledge,!solutions! are!hard! to! find.!This!project! aims! to! study! the!behaviour!of! asphaltene!particles! in! suspensions! through! both! experimental! methods! and! computer!simulations!so!as!to!link!large!scale!problems!with!small!scale!solutions.!The!study!of! the! dynamic! aggregation! behaviour! of! asphaltene! particles! leads! to! the! better!understanding!of!their!molecular!behaviour.!As!a!result!the!particle!sizes!and!their!surface! characteristics! both! in! suspension! and! at! the! oil/water! interface! are!observed! with! a! variety! of! light! scattering! techniques! and! Langmuir! through!analysis.!Molecular!simulations!will!complement!the!experimental!data!and!yield!a!comprehensive! picture! of! asphaltene! behaviour.! This! project! anticipates! attaining!relevant!understanding!of!asphaltene!mechanisms!and!their!link!to!the!oil!industry.!The!starting!point!to!finding!applicable!solutions!to!problems!caused!by!asphaltenes!is!to!fully!understand!their!molecular!mechanisms!and!to!adapt!them!to!large!scale!industrial!processes.!


P17!Nanostructures!on!the!SrTiO3(001)!Surface!'

Y.$Gao,$M.S.J.$Marshall,$A.E.$BecerraBToledo,$L.D.$Marks$and$M.R.$Castell.$

Department'of'Materials,'University'of'Oxford'!Scanning! tunneling! microscopy! reveals! that! following! certain! surface! processing!steps!a!class!of!nanostructures!are!formed!on!the!SrTiO3!(001)!surface.!SrTiO3!single!crystals! doped! with! 0.5wt%! Nb! (nLtype)! were! used! in! these! experiments.! The!sample!surfaces!were!prepared!by!Ar+!ion!sputtering!and!ultraLhigh!vacuum!(UHV)!annealing! in! the! temperature! range! 850! L! 900! C.! Annealing! samples! at! different!temperatures!and!for!different! lengths!of!time!results! in!the!formation!of!different!nanostructures.!These!nanostructures!can!be!classified!as!parallel!packed!nanolines!(dilines,! trilines! and! tetralines),! or! grids! (nanodots! and! waffle! structures).! Upon!extensive!UHV!treatment!anatase!islands!were!formed!on!the!nanostructured!SrTiO3!(001)! surface! after! several! annealing! cycles! at! temperatures! around! 880L900! C.!Moreover,! Auger! electron! spectroscopy! (AES)! and! XLray! photoemission! (XPS)!results! show! that! surfaces! decorated! with! nanolines! are! TiOx! rich.! XPS! spectra!obtained!from!these!three!types!of!nanolines!(dilines,!trilines!and!tetralines)!reveals!a!significant!Ti2+!peak!on!trilines!compared!with!a!small!amount!on!dilines!and!no!Ti2+!peak!on!tetralines.!


P18!Photoluminescence,!photoresponse!and!leakage!current!in!

site!controlled!InAsSb!nanowires!'

A.$Alhodaib,$M.$Thompson,$A.$Aziz,$A.$Krier,$A.R.J.$Marshall$

Lancaster'University'!In!recent!years!many!significant!developments!have!taken!place!in!IIILV!compound!semiconductor! nanostructures.! In! particular,! research! on! InAs! and! InAsSb!nanowires!has!become!a!rapidly!growing! field,!because! these!nanoLmaterials!have!promising! applications! in! infrared! photonics.! Nanoscale! heterostructures! exhibit!unique!structural,!electrical!and!optical!properties!that!can!benefit! from!the!use!of!nanowires,! which! may! indeed! prove! to! be! the! critical! bridge! between! high!performance!photonic!devices!and!low!cost!silicon!substrates.!However,!growth!and!fabrication! of! such! structures! remains! challenging.! In! this! work! we! report! MBE!growth!of! site! controlled! InAsSb!nanowires! (NWs)!on!patterned!Si! substrates.! the!resulting!InAsSb!NWs!which!were!~80!nm!in!diameter!at!330!nm!spacing!with!an!average! NW! length! around! 1.3! µm! shows! good! uniformity! in! areas!where! a! high!proportion! of! sites! have! seeded.! Photoluminescence! (PL)! measurements! confirm!that! antimony! has! been! successfully! incorporated! into! the! wires.! The! PL!measurements!which! have! been! performed! at! 4! K! for! both! InAs! bulk! and! InAsSb!NWs!demonstrate!that!the!NWs!consist!of!an!initial!short!InAs!section!followed!by!a!much! longer! InAsSb! section.! This! results! in! a! PL! spectrum! which! can! be! deLconvoluted! into! two! Gaussian! peaks! corresponding! to! emission! from! the! InAs!section! (2850! nm,! 0.435! eV)! and!more! intense! emission! from! the! InAsSb! section!(3325!nm,!0.37!eV)!respectively.!A!comparison!between!the!peak!from!the!reference!InAs! bulk! sample! (2824! nm,! 0.430! eV)! and! the! peak! from! the! InAs! NW! section!shows!a!blue!shift!of!~5!meV!consistent!with!1D!confinement!in!an!80!nm!diameter!wire.! Assuming! similar! confinement! for! the! InAsSb! NW! the! fraction! of! antimony!incorporated!was!calculated!to!be!6%.!'


P19!Structural!optimization!of!titanium!dioxide!of!(4x1)!

reconstruction!for!photocatalytic!applications!'

K.J.Krupski,$A.$Sanchez,$A.R.$Krupski,$C.F.$McConville$$

University'of'Warwick'!TiO2! is! a! nonLtoxic,! vide! bandLgap! semiconductor! with! three! different! crystal!polymorphs!(brookite,!rutile!and!anatase).!Systems!based!on!TiO2!have!large!variety!of! possible! applications! including! photocatalysis,! heterogeneous! catalysis,!electrocloric! devices! and! solar! cells! for! hydrogen! and! electric! energy! production.!We! have! presented! the! growth! optimization! using! PLD! system.! To! analyze! the!surface!STM,!AFM,!LEED,!XPS,!XRD!and!XRR!measurements,!resulted!flat!surface!is!very! important! to! further! experiments! with! adsorption! of! organic!molecules.!We!report! a! quantitative! structural! determination! of! the! anatase! TiO2! (001)L(4x1)!surface!with! the! use! of! low! energy! electron! diffraction.! An! analysis! of! LEED! I(V)!spectra! from! the! (4x1)! surface! has! been! performed! by! comparing! measured!intensities!with! data! calculated! using! the! automated! CLEED! program.! To! find! the!best! of! atoms! position! of! anatase! TiO2! (001)L(4x1)! was! using! DFT! calculations!(CASTEP!code)!which!give!us!information!of!relaxations.!


P20!The!dependence!of!tungsten!fuzz!growth!on!He!ion!fluence!'

TJ$Petty,$MJ$Baldwin,$MI$Hasan,$RP$Doerner,$JW$Bradley,$$

Department'of'Electrical'Engineering'and'Electronics,'University'of'Liverpool.'Centre'for'Energy'Research,'University'of'California'in'San'Diego.'

!Tungsten! (W)! nanostructure,! commonly! referred! to! as! tungsten! fuzz,! has! been!studied!for!several!years!now.It!manifests!as!a!modification!of!the!W!surface!into!a!layer!of!nanoLscopic!morphology!when!the!surface! is!exposed!at!high!temperature!(~900! K)! to! bombardment! by! energetic! (~30! eV)! helium! (He)! ions.! The!phenomenon!has!been!replicated!numerous!times!in!laboratory!plasmas!and!could!potentially!occur! in! ITER,! the!next! generation! fusion!device!under! construction! in!France.Recent! collaborative! experiments! between! the!University! of! Liverpool! and!the! University! of! California! at! San! Diego! have! been! conducted! with! the! aim! of!examining! the! growth! of! tungsten! fuzz! at! 1120! K,! over! a! wide! range! of! He! ion!fluence! to! better! understand! prior! inconsistencies! in! the! rate! of! growth.! An!expanded! set! of! full! layer! growth! data,! produced! on! four! devices,! has! been! taken!over!a!wide!range!of!He!fluence!(1024L1028!He+/mL2).!The!observed!trend!in!the!data!set! show! a! fluence! dependence! as! well! as! evidence! for! a! necessary! incubation!fluence!before! fuzz! can! form.!A!new!growth! formula! is!proposed!and! the! findings!will!be!presented!at!the!meeting.!


P21!Band!Alignment!of!Ta2O5!on!Sulphur!Passivated!Germanium!

by!XOray!Photoelectron!Spectroscopy!'

M.$Althobaiti[1],$J.$Stoner[1]$,$R.$J.$Potter[2],$I.$Z.$Mitrovic[3],$andV.$R.$Dhanak[1]$$

[1]'Department'of'Physics'and'Stephenson'Institute'of'Renewable'Energy,'[2]'School'of'Engineering,'[3]'Dept.'of'Electrical'Eng.'&'Electronics,'University'of'Liverpool,'Liverpool,'

UK'!Because! of! scaling! limitations,! a! problem! arises! for! silicon! dioxide:! when! its!thickness! becomes! less! than! 1! nm,! leakage! current! is! significantly! increased! in!MOSFET! devices! [1].! Germanium! is! considered! a! lead! alternative! candidate! to!function! as! a! channel! material! due! to! many! reasons,! including! its! high! intrinsic!mobility! compared! to! silicon.! Germanium! channels! offer! approximately! a! double!mobility!gain!of!electrons!and!holes!as!compared!to!Si!channels! [2].!However,!one!should!pay!attention! in!resolving!problems!related! to! the!Ge!before!using! them! in!the!high!performance!filedLeffect!transistor!(FET)!devices.!Among!the!major!issues!related!to!Ge!channels!is!the!quality!of!interfacial!layer.!As!a!low!quality!interfacial!layer! leads! to! substantial! current! degradation,! a! higher! quality! interfacial! layer! is!highly!desirable.In!order!to!obtain!a!high!quality!interfacial!layers!of!Ge,!a!variety!of!materials!and!processes!have!been!employed,!including!highLk!dielectrics,!different!materials! for! metal! gates,! methods! of! deposition! and! post! deposition! annealing!procedures,!and!lastly!but!necessarily!the!passivation!of!the!Ge!surface![3,4].!Several!reports! in! literature! revealed! that! the! above! steps! significantly! affect! the!performance! of! metalLoxideLsemiconductor! (MOS)! [5].! In! this! work,! we! have!characterised!highLk!gate!dielectric!films!of!Ta2O5!deposited!on!Ge!substrates,!which!were!either!untreated!or!sulphurLpassivated!prior!to!deposition!of!the!films.!XLray!photoelectron! spectroscopy! (XPS)! was! used! to! analyze! the! chemical! states! and!composition!of!the!thin!films!of!Ta2O5,!and!determine!the!valance!band!offsets!VBO!with!respect!to!Ge.!!!![1]! S.!Takagi,!R.!Zhang,!M.!Takenaka,!Microelectron.!Eng.!109!(2013)!389.!![2]! Y.!Oshima,!M.!Shandalov,!Y.!Sun,!P.!Pianetta,!P.C.!McIntyre,!Appl.!Phys.!Lett.!94!(2009)!183102.!![3]! K.!W.!Kwon,!C.!S.!Kang,!S.!Park,!H.!K.!Kang,!S.!Ahn,!IEEE!Trans.!Electron!Dev.![4]! P.!A.!Murawala,!M.!Sawai,!T.!Tatsuta,!O.Tsuji,!S.!Fujita,!Jpn.!J.!Appl.!Phys.,!132!(1993)!368![5]! I.!Kim,!S.!D.!Ahn,!B.!W.!Cho,!S.!T.!Ahn,J.Y.!Lee,!J.S.!Chun,!W.!J.!Lee,!Jpn.!J.!Appl.!Phys.,!133!(1994)!6691!


!!

P22:!Transition!state!limited!kinetics!in!stabilizing!intermetallic!

surfaces!

!

A.$AlBMahboob$[1],$M.$Lowe$[1],$H.$R.$Sharma[1],$M.$Armbrüster$[2],$$$$$$$$$$$$$$$$$$$$$J.$T.$Sadowski$[3]$and$R.$McGrath$[1]$

[1]'Department'of'Physics,'University'of'Liverpool,'Liverpool,'UK'[2]'Max[Planck[Institut'für'Chemische'Physik'fester'Stoffe,'Dresden,'Germany'[3]'Center'for'Functional'

Nanomaterials,'Brookhaven'National'Lab,'New'York,'USA.'!Intermetallic!compounds![1,!2]!are!of!great! interest!because!of! their!potential!and!facile!catalytic!activity!for!energy!and!green!applications.!However!the!structure!and!stability!of!the!surfaces!is!crucial!respectively!for!determining!catalytic!activity!and!feasibility! for! applications.! In! spite! of! study! of! intermetallics! over! decades,! the!understanding! the!surface!structure!and! their!stability! is!not! fully!understood!yet.!Among!bimetallic! compounds!ZnPd!was! found! to!be!potential! for!methanol! steam!reforming! [2].! Here! we! will! present! results! obtained! in! our! recent! studies! on!structures! and! stability! of! the! surfaces! of! ZnPd! employing! scanning! tunneling!microcopy! (STM)! and! lowLenergy! electron! microscopy! (LEEM)! experiments.! The!complementary! density! functional! theory! (DFT)! calculation,! DFTLbased!thermodynamic! computation! and! mathematical! modeling! were! employed! to!understand! mechanism! stabilizing! surfaces! observed! in! experiments.!Experimentally! observed! kinetic! stability! of! surfaces! in! this! system! could! not! be!accounted! from! conventional! atomistic! models.! Rather! it! could! rationally! be!accounted) for) a) kinetics) limited) by) transitional) state/structure) (TS)) similar) as)recently( reported( kinetics( in( molecular( systems( [3].( More( specifically,( surface(kinetics(of(attachmentLdetachment)in)ZnPd)are)significantly)affected)by)formation)of)ZnLPd#pairs& instead& of& single& Zn& or& Pd& atoms,&which& results& in& a& stable& surface& at&which%an%atom%(Zn%or%Pd)%is%directly%coordinated%with%alternate%atom%of%the%pair%(Pd%or#Zn#respectively).#Such#atomic#arrangements#determined#by#TS#limited#kinetics#on#surface(make"the"highlyLactive'elements'less'compact'in'the'surface'of'intermetallic'compounds.* The* observed* atomically* less* compact* active* sites* is* also* desired* for*balancing(activity(of(surface(which(essential(for(catalytic(applications.!![1]!J.!A.!Rodriguez,!Surf.!Sci.!Rep.!24,!223L287!(1996).![2]! M.! Armbrüster! et! al.,! Catalysis! Reviews:! Science! and! Engineering,! 55,! 289!(2013).![3]!A.!AlLMahboob!et!al.,!Adv.!Func.!Materials.!23!(2013)!2653;!Adv.!Func.!Materials!(2015)!submitted.!!


!!!

P23:!Templated!quasicrystalline!films!of!single!elements!and!

molecules!

!

H.!R.!Sharma![1],!J.!A.!Smerdon![2],!S.!Hars![1],!S.!Thorn![1],!K.!Nozawa![3],!Y.!Ishii![3],!and!R.!McGrath![1]!

[1]!The!University!of!Liverpool,!Liverpool,!UK![2]!University!of!Central!Lancashire,!Preston,!UK![3]!Chuo!University,!Tokyo,!Japan!

[email protected]!Quasicrystals! are! intermetallic! compounds! possessing! long! range! order! without!periodicity.!Being!different! from! the!periodic! crystals,! quasicrystals! are!promising!for! the! exploration! of! new! epitaxial! phenomena.! We! present! several! interesting!epitaxial!results!observed!on!the!icosahedral!quasicrystal,!which!is!built!by!rhombic!triacontahedral! (RTH)! clusters.! The! results! include! three! dimensional!quasicrystalline!films!of!single!elements![1],!quasicrystalline!molecular!films![2]!and!fivefoldLtwinned!islands!with!magic!heights!influenced!by!quantum!size!effects![3].!!Using! scanning! tunnelling! microscopy! (STM)! and! theoretical! calculations! of!adsorption!energies,!we!find!that!lead!atoms!deposited!on!the!fivefold!surface!of!iLAgLInLYb! occupy! the! positions! of! atoms! in! the! RTH! cluster! and! thus! produce!quasicrystalline!film!in!threeLdimension![1].!This!observation!is!evidenced!in!other!systems! as! well,! namely! Pb! on! the! threefold! iLAgLInLYb! and! In,! Sb! and! Bi! on! the!fivefold!iLAgLInLYb!surface.!!!We! also! found! that!Pentacene!molecules! adsorbs! at! tenfoldLsymmetric! sites! of! Yb!atoms! around! surfaceLbisected! RTH! clusters,! yielding! quasicrystalline! order! [2].!Similarly,!C60! growth!on! the! fivefold! surface!of! iLAlLCuLFe!at! elevated! temperature!produces!quasicrystalline! layer,!where!the!growth!is!mediated!by!Fe!atoms!on!the!surface! [3].! ! The! compatibility! between! the! characteristic! lengths! of! the! substrate!and!the!size!of!adsorbates!leads!to!the!unprecedented!epitaxial!structures.![1]!H.!R.!Sharma,!K.!Nozawa,! J.!A.!Smerdon!et.!al.,!Nature!Communications!4,!2715!(2013).![2]!J.!A.!Smerdon,!K.!M.!Young,!M.!Lowe!et.!al.,!Nano!Letters!14,!1184!(2014).![3]!H.!R.!Sharma,!J.!A.!Smerdon,!P.! J.!Nugent!et.!al.,!The!Journal!of!Chemical!Physics!140,!174710!(2014).!!


!!

Campus'Map!(the!relevant!portion!thereof)!!

!!FB'–'Foster'Building.!The!Mitchell!and!Kenyon!Cinema!and!Scholars!Restaurant!are!both!in!this!building.!8.!Foster!Car!Park!

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