Authors: Petr Dzik, Michal Veselý, Marcela Králová and Michael Neumann-Spallart
Planar, interdigitated photoelectrochemical cells were made by ink jet printing. The electrode fingers had widths from 200 to 1500 μm and were revealed by printing a positive protective polymer mask on FTO glass slides and subsequent etching. One finger family was overprinted by an inkjettable sol-gel composition based on titanium propoxide which was then converted into TiO2 by annealing in air. The device was finalized by printing a masking frame defining its active area. The influence of electrode geometry and titania thickness on the electrochemical properties of resulting cells is discussed in detail. Due to the interdigitated layout, photoelectrochemical response was not suffering from iR drop down to low electrolyte ionic strengths. The photoelectro-catalytic degradation of an aqueous solution of terephthalic acid by UVA illumination and electric bias of 1 V was demonstrated by monitoring the fluorescence of the OH-substituted oxidation intermediate.
Keywords: advanced oxidation process, material printing, inkjet, electrochemistry, water treatment, photocatalysis