Sol-gel-derived spinel Co_3O_4 films and oxygen evolution: Part II. Optimization of preparation conditions and influence of the Nature of the metal salt precursor

摘要

The spinel-type Co_3O_4 films have been prepared on a conductive support using a sol-gel route at 350 deg. C and their physic- ochemical and electrochemical properties towards O_2-evolution on alkaline solutions using TGA/DTG, IR, XRD, SEM, con- ductivity, CV, impedance and Tafel polarization techniques were investigated. The results showed that the nature of the precursor influenced the roughness factor as well as the electrocatalytic activity of the oxide films for O_2-evolution greatly. The ratio of molar concentrations of precursors (i.e. x=[CoSO_4]/[LiOH]) also strongly influenced the electrocatalytic prop- Erties of the catalyst.