We developed a prototype photocatalytic reactor based on a static design, hence tackling a change in the paradigm of photocatalytic reactor engineering. For this, the synthesis of semiconductive oxide nanocavity layers was scaled up to form up to 100 cm2 large photocatalytic surfaces immobilized on rigid elements (e.g. Ti plates). Such design also allows for electrochemical control, if desired, being such photocatalytic surfaces back-contacted by a conductive Ti support. The prototype reactor demonstrated the feasibility of a static design and showed oxide nanocavity layers or nanotubular structures to be more active than classic photocatalytic surfaces such as nanoparticulate films.