Influence of the Mole Ratio of Salt to Alkali on the Surface Structure of SnO2 Thin Film

This work investigated the effects of molar ratio of salt to alkali on the properties of tin oxide nanofilms to provide reference for optimizing its photoelectric conversion efficiency. The tin oxide film grown by hydrothermal method exhibited poor film-forming property. The macroscopic analysis revealed the formation of a thick film. The bonding force to the FTO substrate was poor, its brittle, and easy to fall off. When the molar ratio of salt to alkali was 1:8, the tin oxide film exhibited improved microstructure and large specific surface area, which could benefit electron transport. Moreover, the film showed excellent photoelectric conversion performance. However, mechanical properties, such as adhesion between the tin oxide film and the conductive glass FTO, remain to be improved.