Facile fabrication of visible light driven tin oxide photoanode and its photoelectrochemical water splitting properties

Photoelectrochemical water splitting is a promise way to transfer solar energy to hydrogen as chemical energy carrier. In this paper, visible light driven tin oxide based photoelectrodes were obtained through dipping SnCl2·2H2O EtOH solution on FTO or metal Ti substrate and with further heat treatment process. Photoelectrochemical measurements with three electrodes configuration revealed that this obtained photoelectrode showed n-type responsive properties and the photocurrent density reached mA/cm2 level without any modification under visible light irradiation (λ > 420 nm). XRD, UV–Vis spectrum and control experimental results proposed that the visible light driven mechanism for the tin oxide based photoanode maybe ascribed to Sn4+/Sn2+ transformation and surface oxygen deficiency, and the tin oxide can be denoted as SnO2−x.

► Facile way to prepare tin oxide based photoanode through coating SnCl2·2H2O EtOH. ► This photoanode showed photoelectrochemical water splitting activities under visible light. ► The visible light driven mechanism ascribed to the Sn4+/Sn2+ transformation and oxygen deficient. ► This tin oxide based photoanode can be denoted as SnO2−x. ► It is of great importance to make SnO2 visible light driven.