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9-June-2017 1 Multifunctional Water Soluble Carbon Nano Onions from Flaxseed Oil for Visible Light Induced Photocatalytic Applications and Label Free Detection of Al(III) Ions Trends in Nanotechnology Dr. Kumud Malika Tripathi (Ph.D) Assistant Professor Prof. TaeYoung Kim Group Gachon Bionano Research Institute Department of Bionanotechnology Gachon University, South Korea
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Page 1: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

9-June-20171

Multifunctional Water Soluble Carbon NanoOnions from Flaxseed Oil for Visible Light Induced

Photocatalytic Applications and Label FreeDetection of Al(III) Ions

Trends in Nanotechnology

Dr. Kumud Malika Tripathi (Ph.D)Assistant Professor

Prof. TaeYoung Kim GroupGachon Bionano Research InstituteDepartment of BionanotechnologyGachon University, South Korea

Page 2: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

What are Carbon Nano Onions

In the electron microscope we only see the shell contours

Multilayer giant fullerenes, which consist of multiple concentric graphitic shells to form encapsulated structures

Japanese Scientist, S. Iijima (1980) D. Ugarte (1992) Coined the word “Carbon Onions”

2

Page 3: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

3

Cost Effective Synthesis of Carbon Nano Onions Generally used sophisticated synthetic procedures are expensive, time

consuming and often lead to the formation of metaldeposited/contaminated nano-carbons.

Our approach here is very simple, green and utilizes cost effectivetechnique of wick pyrolysis.

High yield synthesis with ease in reproducibility.

Further oxidation with nitric acid leads to the formation of water solubleversion of carbon nano onions and impart fluorescent.

Amenable to surface modification/functionalization.

Aqueous solubility makes these nano-carbons a potential candidate toexplore their potentials in both environment and biomedical applications.

Page 4: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

Wick

Pyrolysis

[O]

HNO3

CO OH

OHO

O

O O

CO

HO

CO

HO

COHO

CO

OH

C

O

OH

HO

OH

Flaxseed oil Carbon Nano OnionsWater soluble

Carbon Nano Onions

Wick Pyrolysis of

Flaxseed Oil & soot was collected

Refluxed in Conc. HNO3 for

10 h

Purified by washing with

water viacentrifugation

Filter with 0.45, 0.2 & 0.1 µ membrane

Yield 85 %

RepeatedEvaporation on water bath till

pH = 7

Fabrication of Carbon Nano Onions

ACS Sustainable Chem. Eng., 2017, 5 , 3982–3992. 4

Page 5: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

Microscopic Characterization

10 nm

(b)

10 nm

(a)

5 nm

(c)

5

Page 6: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

Spectroscopic Characterization

500 1000 1500 2000 2500 3000 3500

Inte

nsity

(a.u

.)

Wavenumber (cm-1)

15861341

15911335 wsCNOs As-synthesized CNOs

4000 3500 3000 2500 2000 1500 1000 500

3017

123615951720

5501222

1607

3430 As-synthesized CNOs wsCNOs

Tran

smitt

ance

[%]

Wavenumber cm-1

3430

100 200 300 400 500 600 700 800 90050

60

70

80

90

100

Weig

ht (%

)

Temperature (oC)

As-synthesized CNOs wsCNOs

(a) (b)

(c) (d)

10 20 30 40 50 60 70 80

Inte

nsity

(a.u

.)

Angle (2θ)

44

44

23

wsCNOs As-synthesized CNOs

23

(a) FTIR (b) Raman (c) TGA and (d) XRD spectra of CNOs (black line) & wsCNOs (blueline) 6

Page 7: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

Optical Characterization

200 300 400 500 600 700 800 900

0.0

0.1

0.2

0.3

0.4

0.5

0.6

Abso

rban

c e

Wavelength (nm)

246

510 520 530 540 550 560 570 580

Inten

sity

Wavelength (nm)

380 390 400

300 310 320 330 340 350 360

Inten

sity

Wavelength (nm)

335

(a) (b)

(c) (d)

(1) (2)

(a) UV-Vis absorption spectrum and digital image of an aqueous solution of wsCNOs under daylight, (2) under 385 nm λex; (b) PL emission spectra at different wavelengths; (c) PL excitation spectrum at a 523 nm emission wavelength; (d) Fluorescence image of wsCNOs at 488 nm band pass filter, scale bar 20 µm. 7

Page 8: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

Utility of Water Soluble Carbon Nano Onions

In highly selective sensing of trace amount of Al(III) in homogenous aqueous medium with low detection limit.

Photocatalytic degradation of toxic organic dyes for water remediation

8

Page 9: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

Application in photocatalytic dye degradation

(a)(1) (2)

AfterBefore

Green fluorescentwsCNOs /hν

Visible light

UV-Vis absorbance spectra of methylene blue at set 10 minutes of time intervals with (a)wsCNOs and (b) CNOs. Extent of (c) MB photodegradation at different visible lightirradiation time with CNOs and wsCNOs; (d) Plot of ln(C/Co) for MB photodegradationwith CNOs and wsCNOs .

9

Page 10: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

LUMO

HOMO

O2.

O2

Visible light

wsCNOs

h+ h+ h+ h+

e- e- e- e-

H2O

HO.

MBMB

MB .O2

Degradation

ACS Sustainable Chem. Eng., 2017, 5 , 3982–3992.

Visible Light Induced Dye Degradation

10

Page 11: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

CO OH

OHO

O

O O

CO

HO

CO

HO

COHO

CO

OH

C

O

OH

HO

OH

CO OH

OHO

O

O O

CO

O

CO

O

COHO

CO

O

C

O

O

O

O

Al(III)Al(III)

Al(III)

Al(III)

Al(III)

Al(III)

Al(III)

Al(III)

Green fluorescentwsCNOs Fluorescence “Turn-off”

Excitation 390 nm

Emission 531 nm

Al(III)

Fluorescence Quenched

Application in Al(III) Sensing

ACS Sustainable Chem. Eng., 2017, 5 , 3982–3992. 11

Page 12: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

510 520 530 540 550 560 570

Inte

nsity

(a.u

.)

Wavelength (nm)

wsCNOs 10 µL 20 µL 30 µL 40 µL 50 µL 60 µL 70 µL 80 µL 90 µL 100µL

wsCNOs Cl- I-NO3-

SO4--

CH3COO-0.0

0.2

0.4

0.6

0.8

1.0

Rel

ativ

e flu

ores

cenc

e in

tens

ity

wsCNOsNa+ K+

Mg2+Ca2+Ba2+Cr2+Cr3+Cr6+Fe2+Fe3+Cu+Cu2+Al3+Ag+

Cd2+Co2+Hg+

Hg2+Mn2+Ni2+Pb2+Zn2+

0.80

0.85

0.90

0.95

1.00

Relat

ive flu

oresc

ence

inten

sity

510 520 530 540 550 560 570

Inte

nsity

(a.u

.)

Wavelength (nm)

wsCNOs 10 µL 20 µL 30 µL 40 µL 50 µL 60 µL 70 µL 80 µL 90 µL 100µL

(a) (b) (c)

(d) (e)

0 5 10 15 20 25 30 351.0

1.1

1.2

1.3

1.4

1.5

1.6

1.7

1.8

1.9

Concentration of Al(III) (µm)I o

/I

Application in Al(III) Sensing

12

Page 13: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

Conclusion Facile synthetic route for the synthesis of homogenous wsCNOs by traditional

pyrolysis of flaxseed oil as the carbon precursor.

Further oxidation with HNO3 leads to the formation of water soluble version ofCNOs via functionalization with –COOH (surface defects) and further impartfluorescent.

wsCNOs were characterized by TEM, HRTEM, FTIR, Raman, TGA, XRD and zetapotential studies .

Interestingly synthesized CNOs displayed multifunctional applications in sensingand photocatalysis.

wsCNOs used as a fluorescent probe for the sensitive detection of Al(III) ions basedupon florescence “turn-off” technique with a 0.77 µm detection limit.

wsCNOs exhibited excellent visible light driven photocatalytic performancetowards degradation of organic dyes.

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Page 14: Multifunctional Water Soluble Carbon Nano Onions from ...phantomsfoundation.com/.../TNT2017_Tripathi.pdf · Interestingly synthesized CNOs displayed multifunctional applications in

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