Photoelectrochemical cell based on n-CuIn5S8 film as photoanodes for photocatalytic water splitting

• CuIn5S8 films were potentiostatically deposited.
• PEC performance of CuIn5S8 photoanode was altered by varying [Cu]/[In] molar ratio.
• CuIn5S8 is a promising material for solar or photoelectrochemical cells.

In this paper, photoelectrochemical cell has been developed using indium tin oxide (ITO) as the substrate of the CuIn5S8 photoanode and Pt as the cathode. The photoresponse measurements have been conducted in neutral Na2SO4 aqueous electrolyte solutions in three-electrode system and under irradiation of 100 mWcm−2. We have found that the [Cu]/[In] molar ratio has strongly influenced the current voltage (J–V) response. The highest photocurrent density of ca. 8 mA/cm2 with an applied potential of 0.25 V vs. Ag/AgCl has been observed for sample deposited from the molar ratio of ([Cu]/[In] = 0.28). The results show that ternary n-CuIn5S8 thin film electrodes have potential in photocatalytic water splitting application.