Influence of Synthesis Temperature on the Properties of SnO<sub>2</sub> Thin Films via Hydrothermal Precipitation Method

Abstract

To provide reference for optimizing the photoelectric conversion efficiency, we studied the effects of salt–alkali molar ratio on the properties of tin oxide nanofilms. We found that when the hydrothermal temperature was increased to 80 °C, the film growth was not complete. With a hydrothermal temperature of 120 °C, the film became more complete and structured. However, at 160 °C, thick and very irregular tin dioxide (SnO2) crystal particles were deposited on the FTO conductive glass surface. With the increase in heat treatment temperature, crystallization became more and more dense and complete. At 80 °C hydrothermal temperature, the simulated peak of the surface and number of peaks became smaller. However, they significantly increased with a hydrothermal temperature of 120 °C. When the hydrothermal temperature was at 160 °C, the surface simulated peak increased, but the number of peaks decreased. Moreover, the diameter of each peak was greatly increased. The film obtained via the hydrothermal method was relatively pure, and Sn(OH)3 was not completely converted into SnO2.