Solvothermal synthesis of SnO2/graphene composites with improved photoelectric characteristics

SnO2/graphene composites with different contents of graphene were prepared by a solvothermal process using SnCl4 center dot 5H(2)O as Sn precursors, alcohol as solvents and graphene oxide as supports. The composites were characterized by X-ray diffraction, transmission electron microscopy, UV-Vis absorption spectroscopy and Fourier transform infrared spectroscopy, and analyzed by the transient photocurrent response and electrochemical impedance spectra. The content of graphene plays a crucial role in promoting the photoelectric properties of SnO2/graphene due to the effective electron capture and transfer ability upon the insertion of graphene. A higher photocurrent density and lower charge-transfer resistance can be observed for 2% SnO2/graphene. The results indicate that a more efficient separation of photo-induced electron-hole pairs and a faster electron transfer take place at 2% SnO2/graphene.