Study of Photo-cathode Materials for Tandem Photoelectrochemical Cell for Direct Water Splitting

Hydrogen production using water splitting, based on a photoelectrochemical (PEC) process, has attracted considerable attention since the introduction of TiO2 photo-electrodes. A tandem PEC cell, with photo-voltages added from two photo-electrodes, is a possible solution to generate voltage high enough to split water while absorbing more light from a greater part of the solar spectrum.This paper studies some of the potential semiconductor materials that may be suitable for photo-cathode for the tandem PEC cells. The effect of electrolyte pH in changing the photo-cathode material electrochemical properties is analyzed and the effect of semiconductor corrosion property is discussed in this paper. The paper concludes by presenting the results of several semiconductors that have been tested.