MoSx-CdS/Cu2ZnSnS4-based thin film photocathode for solar hydrogen evolution from water

Abstract MoSx was first used as a catalyst instead of noble Pt for a Cu2ZnSnS4-based photocathode. The loading amount of MoSx significantly affected the photoelectrochemical properties of the Cu2ZnSnS4-based photocathode. The photoelectrodeposited MoSx-coated CdS/Cu2ZnSnS4 photocathode presented a superior half-cell solar to hydrogen conversion efficiency of above 2.3% and a long-term stability over 10 hours in neutral aqueous solution. In addition, the pH value of the electrolyte solution determined the photocurrent, onset potential and photoelectrochemical stability of the MoSx-CdS/CZTS-based photocathode. The MoSx-CdS/CZTS photocathode worked efficiently and stably in acidic solutions and gave the highest half-cell solar-to-hydrogen conversion efficiency above 3% in pH 3 acidic buffer solution, with a photocurrent density under 0 VRHE and an onset potential at approximately 18 mA/cm2 and 0.6 VRHE, respectively.