Characterization of electrolytic tin dioxide deposition on Pt for lithium ion battery applications

Abstract

By using cathodic electrodeposition, three structures of Sn, Sn 6O 4(OH) 4 and SnO 2 could be obtained in the 1 mM SnCl 2 aqueous solution for various aeration periods in air. In order to obtain the pure SnO 2 coatings as the anode of thin-film lithium ion battery, the aeration should proceed for 10 days to oxidize tin valence from stannous to stannic in SnCl 2 aqueous solution. The coating films were further annealed and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR), thermogravimetric–differential analysis (TGA), Raman spectroscopy, and cyclic voltammetry (CV). The as-coating SnO 2 film containing 2.4 H 2O in the pristine state could be dehydrated at 300 °C for 2 h, or at 250 °C for 12 h. The crystallinity and surface coarsening of the coating films were promoted with increasing annealing temperature. The dehydrated SnO 2 film used as the anode of a lithium battery showed a reversible capacity as high as 500 mA h/g after 10 cycles at a discharging rate of 0.2 C, which could result from the nano-sized microstructure of coating film.