Cathodic deposition of SnO2 layers on transparent conductive substrates and their photoelectrochemical activity

[Display omitted] •SnO2 thin films were obtained by electrodeposition on FTO-coated glass.•Co-deposition of metallic Sn was observed at the most negative potentials.•Co-deposited Sn can be successfully converted to the oxide phase by annealing.•The photoelectrochemical activity of layers formed at various conditions is discussed. Tin dioxide (SnO2) films deposited on transparent conductive substrates have been considered as promising candidates for photoelectrochemical and photovoltaic applications due to their promising properties such as high electron mobility, stability, and favorable band edges positions. Therefore, a simple electrochemical approach based on the cathodic deposition of SnO2 on a conductive glass substrate was proposed. SnO2 layers were obtained by electrodeposition from SnCl2 solution containing HNO3 at various potentials (from −0.6 V to −1.0 V vs. SCE) for various durations (from 5 min to 180 min). The obtained materials were then annealed in air at 400 °C and characterized. The co-deposition of the metallic phase at the most negative potential was confirmed. However, it was successfully converted to the oxide phase by thermal treatment. The photoelectrochemical activity of the materials during illumination with monochromatic light from the range between 250 and 500 nm was studied. The higher photocurrents were generated by annealed layers, and the most promising photoelectrochemical properties were observed for the sample deposited at −0.8 V vs. SCE for 180 min. It is expected that such a simple electrochemical approach can be an effective strategy for the fabrication of highly efficient photoanodes for photoelectrochemical and photovoltaic applications.