photooxidation of tris in a photoelectrochemical biofuel cell

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1

Photooxidation of Tris in a Photoelectrochemical Biofuel Cell

Marcin S. FilipiakPiotr GreskowiakAdrianna ZloczewskaRobert LynchMartin Jönsson-Niedziolka

Institute of Physical ChemistryPolish Academy of SciencesWarsaw, Poland

Martin Jönsson-Niedziólka, martinj@ichf.edu.pl

Institute of Physical Chemistry PAS, Warsaw Poland

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Outline

• Photoelectrochemical biofuel cells

• Our system and preparation of TiO2 NT electrodes

• Some difficulties

• Tris(hydroxymethyl)aminomethane oxidation

• Conclusions

Institute of Physical Chemistry PAS, Warsaw Poland

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Yang, J. et al., J. Power Sources 248, 660–667 (2014).

Photoelectrochemical Biofuel Cell

Institute of Physical Chemistry PAS, Warsaw Poland

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Brune, A. et al., Langmuir 20, 8366–71 (2004).

TiO2 anode with 5-(4-carboxyphenyl)-10,15,20-tris(4-methylphenyl)porphyrin. Anode compartment with 0.25 M Tris at pH 8 (adjusted with HCl) that contained 0.1 M KCl as a supporting electrolyte.4.0 mM NADH, 0.10 M glucose, and 0.5 units/mL GDH under an argon atmosphere.Three electrode setup.

Photoelectrochemical Biofuel Cell

Institute of Physical Chemistry PAS, Warsaw Poland

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TiO2 nanotube anode and air-breathing biocathode

Institute of Physical Chemistry PAS, Warsaw Poland

Zloczewska, A. & Jönsson-Niedziolka, M., J. Power Sources 228, 104–111 (2013).

66Institute of Physical Chemistry PAS, Warsaw Poland

Anodisation of TiO2 nanotubes (TNTs)

• Electropolished titanium sheet • 0.75% HF solution in ethylene glycol,• H2O content - 9.985% v/v• 100 V• 1 h• after anodization – 3 h of 450°C annealing

J. M. Macák et al., Angew. Chem. Int. Ed. (2005) 44 (14), p. 2100–2102

77Institute of Physical Chemistry PAS, Warsaw Poland

0.6% v/v HF

1.0% v/v HF

88Institute of Physical Chemistry PAS, Warsaw Poland

Setup

photoanode

TiO2 NT

biocathodeTORAY|

(BOD+SWCNT-PTSA+MTMOS)

Nafion membrane

0.1 M phosphate buffer pH 8

0.1 M phosphate

buffer pH 4.8

99Institute of Physical Chemistry PAS, Warsaw Poland

Zloczewska, A., PhD Thesis (2013).

Some strange results

Black – Sensitised TNTs; 4 mM NADH, 15 Units GDH dm−3 and 1 M glucose

Grey – bare TNTs in buffer.

Diamonds grown for 4 hours, triangles 1 h.

1010Institute of Physical Chemistry PAS, Warsaw Poland

What‘s going on?

Illumination

Glucose is adsorbing UV.- removing all the biostuff – glucose sensorNot suitable porphyrin Large background currents in

enzyme experiments

Han, L., et al., Chem. Commun. 48, 6103–5 (2012).

1111

Large background current

Institute of Physical Chemistry PAS, Warsaw Poland

(a)glucose (b)glucose, but no sensitizer, GDH and

NADH (c) no glucose(d)in the dark.Yang, J. et al., J. Power Sources 222, 344–350 (2013).

Han, L., et al., Chem. Commun. 48, 6103–5 (2012).

1212Institute of Physical Chemistry PAS, Warsaw Poland

Tris photoelectrocatalysis on TNT

1313Institute of Physical Chemistry PAS, Warsaw Poland

Tris photoelectrocatalysis on TNT

Tris is photo-oxidised by hydroxyl radical attack

Diesen, V. & Jonsson, M., J. Adv. Oxid. Technol. 15, 392–398 (2012).

Langmuir-Hinshelwood model

KLH = 295 M-1

1414Institute of Physical Chemistry PAS, Warsaw Poland

Photoelectrochemical biofuel cell

0.0 0.3 0.6 0.9 1.2 1.50

100

200

300

400

500486 A/cm

2

1.36 V

1.07 V

366 A/cm2

j /

A/c

m2

E vs. Ag/AgCl / V

0.25 M TRIS

buffer

2 M MeOH

0.0 0.3 0.6 0.9 1.2 1.50

50

100

150

200

250

138.31 W/cm2

(0.61 V)

222.5 W/cm2 (0.73 V)

P / W

/cm

2

E vs. Ag/AgCl / V

buffer

0.25 M TRIS

2 M MeOH

Very similar characteristics to published PECBFC with enzymatic regeneration system.

1515Institute of Physical Chemistry PAS, Warsaw Poland

Conclusions

• Tris can be efficiently photoelecrooxidized on the titania

based electrode

• We made a TNT based PECBFC with decent

performance.

• Tris can act as a quite efficient fuel in

photoelectrochemical biofuel cell, but maybe it's not the

best idea

• Main conclusion – be careful with your buffers, they are

not always nice inert backgrounds.

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Dr Ada ZloczewskaDr Robert LynchUniversity of Limerick

Marcin Filipiak

1616Institute of Physical Chemistry PAS, Warsaw Poland

Martin Jönsson-Niedziólka, martinj@ichf.edu.pl, www.charge-transfer.pl

Thank you for your attention

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