Planar, interdigitated photoelectrochemical cells were made by ink jet printing. The electrode fingers had widths from 200 to 2000 mu m and were revealed by printing a positive protective polymer mask on FTO (F:SnO2) covered glass slides and subsequent etching. One finger family was covered by TiO2, made by using an ink containing the precursor inside inverted micelles and annealing in air. 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 1V was demonstrated by monitoring the fluorescence of the OH-substituted molecule. (C) 2014 Elsevier B.V. All rights reserved.