Effects of starting precursor and calcination condition on phase formation characteristics of Mg4Nb2O9 powders

• Main Author: Ananta S.
• Format: Article
• Language: English
• Published: 2014
• Online Access: http://www.scopus.com/inward/record.url?eid=2-s2.0-3242672456&partnerID=40&md5=357aeaac06605562f6a4d33f8d1b6b8c; http://cmuir.cmu.ac.th/handle/6653943832/6809
• Institution: Chiang Mai University

A corundum-like phase of magnesium niobate, Mg4Nb 2O9 (MN), has been synthesised by a rapid vibro-milling technique. Both magnesium carbonate and magnesium carbonate hydroxide pentahydrate have been investigated as magnesium precursors, with the formation of the Mg4Nb2O9 phase investigated as a function of calcination temperature, dwell time and heating rate by DTA and XRD. Moreover, morphology and phase composition have been determined via SEM and EDX techniques. The starting precursor and calcination temperature have been found to have a pronounced effect on the phase formation of the calcined Mg 4Nb2O9 powders. It is seen that optimisation of calcination conditions can lead to a single-phase Mg4Nb 2O9 in a hexagonal form. Among the two magnesium precursors, it is seen that the formation temperature of single-phase Mg 4Nb2O9 powder was lower for the synthetic method employing magnesium carbonate hydroxide pentahydrate. © 2004 Published by Elsevier B.V.