Influence of thermal treatment on the ion-storage capacity of Ce oxide and Ce-V mixed oxide films

Thin films and the corresponding xerogels of CeO₂ and Ce-V mixed oxides with a molar ratio equal to 2 (Ce/V=2) were prepared from CeCl₃·7H₂O and NH₄VO₃ precursors using the sol-gel route and the dip-coating technique. The thermal decomposition of both forms of samples (thin films and xerogels) were studied by dynamic TG and DSC in two different atmospheres (air and argon). For the thermal studies the thin films were deposited on aluminium foil to reduce the unfavourable substrate to film mass ratio S/F, which is a consequence of using a glass substrate. The mode of heat treatment in a tube furnace of films deposited on conductive glass was defined from the TG curves of the films. The influence of annealing conditions (temperature, atmosphere and time) on the charge capacity of the films during application of the cycling process is reported.