Effect of calcination conditions on phase formation and particle size of zinc niobate powders synthesized by solid-state reaction

A columbite-like phase of zinc mobate, ZnNb2O6, has been synthesized by a solid-state reaction via a rapid vibro-milling technique. The formation of the ZnNb2O6 phase in the calcined powders has been investigated as a function of calcination conditions by TG-DTA and XRD techniques. Morphology, particle size and chemical composition have been determined via a combination of SEM and EDX techniques. It has been found that single-phase ZnNb2O6 powders were successfully obtained for calcination condition of 600 degrees C for 2h or 550 degrees C for 6h with heating/cooling rates of 30 degrees C/min. Clearly, this study has demonstrated the potentiality of a vibro-milling technique as a significant time-saving method to obtain single-phase ZnNb2O6 nanopowders (similar to 50-300nm) at low calcination temperature. (c) 2006 Elsevier B.V All rights reserved.