BEHAVIOR OF A FLUORINE-DOPED TIN OXIDE ELECTRODE - A STUDY BY QUARTZ-CRYSTAL MICROBALANCE IN PROPYLENE CARBONATE

Fluorine-doped tin oxide (FTO) was deposited onto a gold electrode eva porated onto a quartz crystal. The FTO material was cycled in propylen e carbonate in the presence of 1 M LiClO4. Voltammetric and gravimetri c responses of the FTO electrode were recorded between + 2.75 and + 0. 75 V vs. Li/Li+ for 180 cycles. During the first few cycles, reduction of trace water was predominant so that the growth of a film of lithiu m hydroxide was instantaneous. This layer was porous so that ions ente ring and leaving this layer could explain the presence of the typical doping-dedoping electrochemical curves.