Design of an electrolytic cell for a monolithic photovoltaic-electrolytic hydrogen generation system: The electrode aspects

The combination of a photovoltaic (PV) and an electrolytic cell into one single system, a monolithic PV-electrolytic cell, has been suggested as an efficient solar hydrogen generation system. In this study, we demonstrate an efficient prototype electrolysis system applied to a monolithic PV-electrolytic cell. Specifically, the relatively large unit cell (active area of 36 cm ²) used in the study made it possible to directly measure in volume the amount of hydrogen and oxygen generated. To enhance the activity of the electrodes we introduced channels, Co ₃O ₄ film, and Pt particles on stainless steel (SUS) substrates. The highest hydrogen production rate was obtained in the system in which Co ₃O ₄ electrocatalytic film on a SUS foil and Pt particles on a SUS plate with channels were used as an anode and a cathode, respectively.