Design of a photochemical water electrolysis system based on a W-typed dye-sensitized serial solar module for high hydrogen production

A W-typed dye-sensitized serial solar module (W-typed DSSM) was designed for hydrogen production from water electrolysis. The optimal thickness and width of the TiO2 electrode film were 12 μm and 5 mm, and the optimal thickness of Pt counter electrode film was 4 nm, respectively. The photocurrent density, open circuit voltage, and fill factor were 2.13 mA cm−2, 3.51 V, and 0.61, respectively, for a serial module assembled from five unit cells, which resulted in an overall conversion efficiency of 4.56%. The obtained voltage increased with increasing number of unit cells connected, and was 3.51 V in the five column fabricated W-typed DSSM. 2.1 mL h−1 of hydrogen gas was emitted when a W-typed DSSM assembled from five columns was connected to carbon electrodes in a water electrolysis system. The rate of hydrogen evolution in the five columned W-typed DSSM was 0.00213 L h−1. Therefore, the actual light-hydrogen conversion was calculated to be 2.02%.