Abstract：The Co₄Nb₂O₉ precursor gel was successfully synthesized via the sol-gel method with cobalt nitrate and niobium pentoxide as raw materials, citric acid as complexing agent and ethylene glycol as esterifying agent, and ultrafine Co₄Nb₂O₉ powders can be obtained after sintering process. The crystal structure, apparent morphology and chemical composition of the samples were characterized by XRD, SEM and EDS, respectively. The result shows that submicron Co₄Nb₂O₉ powders can be obtained after the precursors were calcined at 900 ℃, which possess pure phase and good crystallization.

Keywords：sol-gel process; Co₄Nb₂O₉; superfine powder