A SOL-GEL ROUTE FOR THE PREPARATION OF CO3O4 CATALYST FOR OXYGEN ELECTROCATALYSIS IN ALKALINE-MEDIUM

In order to increase the surface area of oxide electrocatalysts we hav e studied anew preparation method for Co3O4 spinel-type oxides. We hav e employed a sol-gel route, where the solution of Co(II)-carbonate in propionic acid is heated to form a resinic cobalt propionate. The powd er obtained after pouring liquid nitrogen on the gel is immediately th ermically treated up to 260-degrees-C to obtain the spinel pure phase Co3O4, as confirmed by X-ray diffractometry. SEM studies have shown th at this precursor phase is near to monodisperse with 2-4 mum particle size. The oxide obtained this way has a BET surface area higher than t he oxides prepared by the nitrate decomposition route. However, taking into account the roughness factor, the electrocatalytic activities ar e similar. (C) 1994 Academic Press, Inc.