Michael W. TauschPhotochemistry

Polymers & CompositesChemical Education

• Why Photoprocesses in MatSci? • Basic Concept & Classification• Experimental Approaches in SciEd

Nano-Electronics

[Patrick Görrn] Conjugated Polymers in Education

[Tausch-Group]

Synthesis of Conjugated Polymers

[Ulli Scherf]

The 8 Group Leaders

Bergische Universität Wuppertal

Devices: Solar Cells, OLEDs & Co

[Thomas Riedel]

0 1

Photoprocesses in

Material Sciences

Life Science, e.g.:• in the photoreactor atmosphere

• in the photoreactor leaf

• in the photoreactor eye

• in the photoreactor skin

• in other natural systems

Material Science e.g.:• in photovoltaic cells

• in LED‘s and OLED‘s

• in research facilities

• in technical photoreactors

• in microelectronic devices

• in medicine

• in other man-made systems

Photoprocesses in

Material Sciences

Saving of Energy, e.g.:• in LED‘s und OLED‘s

• in solar reactors

• in climat control units with photochromic

and electrochromic windows

• in phototechnical procedures

Supply of Electrical Energy

from Sun Light, e.g.:• in photovoltaic cells

• in photoelectrochemical cells

• in fluorescence collectors (concentrators)

Sun Light Conversion and

Chemical Storage, e.g.:• in solar hydrogen, methane, methanol ..

• artificial photosynthesis products

Photoprocesses in

Material Sciences

2,5 ∙ 1022 J

3 ∙ 1024 J

100

Global Reserves (Mineral Oil, Natural Gas,

Coal, Uranium)

Annual Solar Radiation

Photoprocesses in

Material Sciences

Solar: 100 000 TW

Wind: 14 TW

Ocean Currents: 0.7 TW

Biomass: 5-7 TW

Hydroelectric: 1.2 TW

Geothermal: 1.9 TW

Source: Konarka, Arthur Norcik

Photoprocesses in

Material Sciences

Quelle: WBGU (Wiss. Beirat Globale Umweltveränderungen) des BMBF; September 2013

The Scinetific Advisory Board of the German Federal Ministery of Education and Research

Photoprocesses in

Material Sciences

Innovative Contents ► Experiments ► Teaching Concepts ► Printed and Eletronic Media

„A pretty Experiment

quite often is more precious

than twenty equations

bred in the thinking retort.“A. Einstein1955

E = mc2

www.chemiedidaktik@uni-wuppertal.de > Teaching Photochemistry

Photoprocesses in

Material Sciences

Requirements for a „pretty“ Experiment: ►appealing & beautiful ► instant & inexpansive

►secure & clean ► innovative & grean ► …

►didactically concise & scientifically consistent

www.chemiedidaktik@uni-wuppertal.de > > > Teaching Photochemistry

Photoprocesses in

Material Sciences

The Jablonski Diagram

Paradigm (pattern of thinking)

pensiamiento):„The „photo“ part of molecular photochemistry is a historical prefix and is now

too restrictive. It is now clear that electronically excited states of molecules

are the heart of all photoprocesses. The excited state is in

fact an electronic isomer of the ground state.“N. J. Turro

Modern Molecular Photochemstry. Benjamin/Cummings, N.Y. (1978)

Photoprocesses in

Material Sciences

Light

S1→S0T1→S0

Luminescence: F, P, CL, EL, ECL

Energy transfer

Electron transferFurther reaction

types

Isomerization

Photovoltaics

Photoprocesses in

Material Sciences

Photoprocesses in

Material Sciences

Luminescence: F, P, CL, EL, ECL

Light

or other Energies

Energy Transfer/ Photosensitization

Electronen Transfer / PhotoredoxFurther Rections

Inorg. & Org. Photovoltaic Cells

Isomeri zations (E/Z and others)

• Coating of fluorescent lamps

• LED‘s for Lamps and displays

• OLED‘s for Lamps and displays

• Unforgeable documents & money

• Luminescent dyes for textiles etc.

• Fluorescence collectors

• Immunoassays (med. diagnose)

• Photodynamic therapy

• Fluorescence microscopy)

• Analytic methods (CL-Assay,

„Green Fluorescent Protein“

„Single Molecule Spectroscopy“)

Photoprocesses in

Material Sciences

Photoprocesses in

Material Sciences

Isamu Akasaki, Hiroshi Amano and Shuji Nakamura,

Nobel Price in Physics 2014 for the invention of blue LEDs

Stefan Hell, Eric Betzig and William Moerner,

Nobel Price in Chemistry for the invention of the STED-Nanoscopy

Photoprocesses in

Material Sciences

Paradigm: Atomic and molecular systems can exist in the electronic ground state

as well as (even for a short time) in electronically excited states.

M.Tausch, M. v. Wachtendonk , C. Bohrmann-Linde, S. Krees (Hrsg.), CHEMIE 2000+, C.C.Buchner, Bamberg (2007…2014)

The energy level model for molecules – A core concept in chemistry

excited state T1

τ = 10-2 – 102 s

excited state S1

τ = 10-9 – 10-8 s

Fluorescence

Phosphorescence

Exchange

of heat

lowest

unoccupied

energy level

highest

occupied

energy level

ground state So

M.T., D. Paterkiewicz, PdN-Chemie 36, 14 (1988); M.T., A. Grolmuss, M. Woock, PdN-Physik 47, 10 (1998); M.T., F.Gärtner, PdN-ChiS, 53, 20 (2004)

Photoprocesses in

Material Sciences

Flu

ore

scence

E

HOMO

Absorp

tion

LUMO

M.Tausch, M. v. Wachtendonk , C. Bohrmann-Linde, S. Krees (Hrsg.),

CHEMIE 2000+, C.C.Buchner, Bamberg (2007…2014);

Animationen unter www.chemiedidaktik.uni-wuppertal.de

Photoprocesses in

Material Sciences

Absorp

tion

Phosphore

scence

E

HOMO

LUMO

M.Tausch, M. v. Wachtendonk , C. Bohrmann-Linde, S. Krees (Hrsg.),

CHEMIE 2000+, C.C.Buchner, Bamberg (2007…2014);

Animationen unter www.chemiedidaktik.uni-wuppertal.de

Photoprocesses in

Material Sciences

Folie 20Nico Meuter

PhotolumineszenzChemie und ihre Didaktik

Videos: & Animations: www.chemiedidaktik.uni-wuppertal.de > Teaching photochemistry

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0,9

1

380 430 480 530 580 630

Em

iss

ion

[a

. u

.]

Weavelength [nm]

Emission Spectra ofAesculine

in Tartric Acid Matrix

red shift ≈100 nm

red shift ≈100 nm

Photoprocesses in

Material Sciences

Folie 21Nico Meuter

PhotolumineszenzChemie und ihre Didaktik

Videos: & Animations: www.chemiedidaktik.uni-wuppertal.de > Teaching photochemistry

excited state T1

τ = 10-2 – 102 s

excited state S1

τ = 10-9 – 10-8 s

Fluorescence

Phosphorescence

Exchange

of heat

Video: Phosphorescence at different temperatures

Photoprocesses in

Material Sciences

Organic Photo ElectronicsProf. Dr. M. W. Tausch & Jun.-Prof. Dr. Amitabh Banerji

22/27

Photoprocesses in

Material Sciences

Nobel Price in Chemistry, 2000

Polythiophene

Poly(phenylene)vinylen

Polyfluorene

Alan MacDiarmid, Hideki Shirakawa, Alan Heeger

Polyacetylene

Organic Photo ElectronicsProf. Dr. M. W. Tausch & Jun.-Prof. Dr. Amitabh Banerji

23/27

Photoprocesses in

Material Sciences

A. Banerji, U. Scherf, M. T.: "Classroom Experiments and Teaching Materials

on OLEDs with Semiconducting Polymers", Education Quimica, 24 (1), 17 (2013)

*

*

LUMO

HOMO

LUMO

HOMO

≈CBConduction

Band

≈ VBValence

Band

n

Organic Semiconductors - Energy Band Model

Organic Photo ElectronicsProf. Dr. M. W. Tausch & Jun.-Prof. Dr. Amitabh Banerji

24/27

+MBBA

+ -

-+

-+

Ph

oto

n

Anode CathodeSemiconductor

-

-+

-+

Anode CathodeSemiconductor

+-

+- -

-

Photoprocesses in

Material Sciences

•PPV [Poly(p-vinylene)phenylene ]•ITO- or FTO-Glasses•Galinstan (Alloy of Ga-In-Sn)

•P3HT [Poly[3-hexyl)thiophene]•PCBM [Fullerene-Derivative]•ITO- or FTO-Glasses•Galinstan (Alloy of Ga-In-Sn)

ExcitonExciton

Ph

oto

n

Electric Energy → Light Light → Electric Energy

Organic Photovoltaic Cells OPV .Heliatek, DresdenActually(2016): 13,2% Efficency; 50% Transparency

Curved OLED-TV, SamsungActually(2016): Screen Diaoganal up to 60 ynches152 cm)

Photoprocesses in

Material Sciences

A. Banerji, M. T., PdN-ChiS 59 (4), 42 (2010); A. Banerji, U. Scherf, M. T., Chemkon, 19 (1), 7 (2012);

A. Banerji, U. Scherf , M. T. , Educ. Quimica , 24 (1), 17 (2013)

Easy OLED

Standard OLED

Flexi OLED

Quick OLED

www.chemiedidaktik.uni-wuppertal.de

Flash OLED

PPV-Der.

Photoprocesses in

Material Sciences

J.C. Hummelen, PdN-ChiS, 59 (2) 31 (2010); A. Banerji, M. T., U. Scherf, Chemkon, 19 (1), 7 (2012); M. Zepp, M.T., PdN-ChiS, 64 (1) 18 (2015))

www.chemiedidaktik.uni-wuppertal.de > Flash Animationen

Video OPV

Flash OPV

P3HT

PC61BM

Photoprocesses in

Material Sciences

I. N.Rendon-Enriquez, U. Scherf, , M. T., PdN-ChiS , 65 (8), 34 (2016)

On

Off

OO

O

CH3

Propylencarbonat (PC)

CH3

CH3

CH3

N+

CH3

ClO4

-

Tetrabutylamoniumperclorat (TBAP)

O

OH

CH3

CH3

CH3 CH3

CH3

Triton X-100

H3COCH3CH2

O

OCH3

CH2O

O

OCH2

O

n

2,2-Dimethoxy-2-Phenyl-Acetophenon (DMPA)

Poly(ethylenglycol)Diacrylat (DA)

OH

OH OO

OHOH

O

Zitronensäure (ZS)

O3

-S

S

NN

NS

N

CH3

CH3

-

3OS

ABTS

S S

NS

N

S S

NS

N

n

4,7-Dithiophen-2,1,3-benzothiadiazol (DTBT)

Poly(4,7-Dithiophen-2,1,3-benzothiadiazol (PDTBT)

S

O O

3,4-Ethylendioxythiophen (EDOT)

S

O O

S

O O

S

O O

n

Poly(3,4-Ethylendioxythiophen) (PEDOT)

NH

Pyrrol (Py)

Polypyrrol (PPy)

NH

NH

n

S

O

O

O-

Lithiumtrifluormethansulfonat

F3C Li+

(TRIF-)

OO

O

CH3

Propylencarbonat (PC)

CH3

CH3

CH3

N+

CH3

ClO4

-

Tetrabutylamoniumperclorat (TBAP)

O

OH

CH3

CH3

CH3 CH3

CH3

Triton X-100

H3COCH3CH2

O

OCH3

CH2O

O

OCH2

O

n

2,2-Dimethoxy-2-Phenyl-Acetophenon (DMPA)

Poly(ethylenglycol)Diacrylat (DA)

OH

OH OO

OHOH

O

Zitronensäure (ZS)

O3

-S

S

NN

NS

N

CH3

CH3

-

3OS

ABTS

S S

NS

N

S S

NS

N

n

4,7-Dithiophen-2,1,3-benzothiadiazol (DTBT)

Poly(4,7-Dithiophen-2,1,3-benzothiadiazol (PDTBT)

S

O O

3,4-Ethylendioxythiophen (EDOT)

S

O O

S

O O

S

O O

n

Poly(3,4-Ethylendioxythiophen) (PEDOT)

NH

Pyrrol (Py)

Polypyrrol (PPy)

NH

NH

n

S

O

O

O-

Lithiumtrifluormethansulfonat

F3C Li+

(TRIF-)

CH2O

O

OCH2

O

+.CH3

CH2O

O

OCH2

.

On n

Poly(ethyleneglycole)diacrylate

Photoprocesses in

Material Sciences

On

Off

I. N.Rendon-Enriquez, U. Scherf, , M. T., PdN-ChiS , 65 (8), 34 (2016)

OFF

ONAFM image

Roughness: xy nm:

Photoprocesses in

Material Sciences

Michael M. Lerch, Mickel J. Hansen, Gooitzen M. van Dam, Wiktor Szymanski and Ben L. Feringa,

Angew.Chem. Int. Ed., 2016, ASAP (DOI: 10.1002/anie.201601931) (DOI: 10.1002/anie.201601931

Feringa‘s Nano-Motor

Photoprocesses in

Material Sciences

Nobel Price Chemistry 2016

Ragnar S. Stoll, Stefan Hecht, Angew.Chem., 122 (30), 5176 (2010)

… a photoswitchable

(thermal) catalyst

accessible

basic/nucleophilic

center

Photoprocesses in

Material Sciences

S. Shinkai et al. Bull. Chem. Soc. Jap., 60, 1819, (1987)

V. Ramamurthy, Photochemistry in Organized and Constrained Media, VCH, (1991)

D. Wöhrle, M.W. Tausch, W.-D. Stohrer, Photochemie, Wiley-VCH, (1998)

… a Molecular

Trojan Horse

… a Molecular „Vise“

(„Screw Matrix“)

Photoprocesses in

Material Sciences

E.D.Bergmann, A.Weizmann, E.Fischer, JACS, 72, 5009 (1950) ; M. T., Chemkon, 3, 123 (1996);

M. T. Education Quimica, 16 (4), 529 (2005) S. Krees, PdN-ChiS, 62 (8), 35 (2013); M. T., PdN-ChiS, 64 (1) 5 (2015)

DIN A5 ca. 4 €

Polystyrol

Toluol

PET-Folie

Light (400 nm)

Heat; Light (550 nm)

Merocyanine C19H18O3N2

10

Spiropyrane C19H18O3N2

► Molecular Switch: Spiro../Mero..

► Polymer-Matrix: Poly-Sty vs. Poly-VA

► Photochemistry vs. Thermochemistry

► Aggregated Induced Luminescence

► Molecular Logics with „1“ and „0“

Photoprocesses in

Material Sciences

Toluene

Spiropyrane

Plastic Foil (PET)

Polystyrene

Photoprocesses in

Material Sciences

Water, T = 60° C Ice & Water, T = 0° C

Erasing Storing

OverwritingWriting

S. Krees PdN-ChiS 61 (2) 18 (2012);

S. Spinnen, M. Essers, S. Krees, M. T.

PdN-ChiS 63 (2), 35 (2014);

N. Meuter, M. T. Photo-Mol ,

Hedinger, Stuttgart (2015),

Photoprocesses in

Material Sciences

Angeregter

Zustand

Grundzustand

Thermische Reaktion vs. photochemische Reaktion

M. W.Tausch, Chemkon, 3, 123 (1996)

Thermischer

Reaktionsweg

Photochemischer

Reaktionsweg

M.Tausch, M.v.Wachtendonk (Hrsg.), CHEMIE 2000+, C.C.Buchner, Bamberg (2007…2010)

E.D.Bergmann, A.Weizmann, E.Fischer, JACS, 72, 5009 (1950)

Photochemical

Reaction

Pathway

Thermal

Reaction

Pathway

Reaction Coordinate

www.chemiedidaktik.uni-wuppertal.de

Photoprocesses in

Material Sciences

λ < 400 nm

S. Spinnen, M. T., PdN-ChiS 64 (6), 46 (2015)

Orthogonal

Solvents

To-

lu-

ene

Ethylene-

glycole

Photoprocesses in

Material Sciences

Beng Zhing Tang et al. „Aggregation-Induced Emission:

The Whole Is More Brilliant than the Parts“, Adv. Mat. DOI 10.1002 (2014)

S. Spinnen, M. Essers, S. Krees, M. T., PdN-ChiS, 63 (2), 35 (2014)

S. Spinnen, M. T., PdN-ChiS 64 (6), 46 (2015)

Stokes Shift:130 nm

Stokes Shift:130 nm

Photoprocesses in

Material Sciences

Chemie 2000+ , C.C. Buchner, Bamberg (2002..2014)

S. Spinnen, M. Essers, S. Krees, M. T., PdN-ChiS, 63 (2), 35 (2014)

S. Spinnen, M. T. PdN-ChiS, 64 (6), 46 (2015)

polar

nano-environment

(Nitrocellulose, PVA)

Mero

Spiro

non polar

nano-environment

(Polystyene)

SpiroMero

Mero

Photoprocesses in

Material Sciences

S. Spinnen, M. T., (2016) unpublished

Absorption Emission

523 nm 632 nm

Absorption Emission

395 nm 510 nm

Input 1

Input 2

Output

Photoprocesses in

Material Sciences

www.chemiedidaktik.uni-wuppertal.de

Chemie und ihre Didaktik

Michael W. Tausch

Prof. Dr. Claudia

Bohrmann-Linde

Prof. Dr. Simone Krees

Prof. Dr. Amitabh Banerji

Dr. Ralf-Peter Schmitz

Dr. Bernd Rohe

Dr. René Krämer

Heidrun Geller

Yasemin Yurdanur

Nico Meuter

Maria Heffen

Melanie Zepp

Heiko Hoffmann

Sebastian Spinnen

Ibeth Rendón Enríquez

Heiko Hoffmann

Ingrid Reisewitz-Swertz

Renate Gärtig

David Nietz

Frederic Posalla

Saskia Ruckebier