Single‐Calcination Synthesis of Pyrochlore Free Pb(Mg_1/3Nb_2/3)O₃ Powders Using Particle‐Coating Method

Abstract

Using two-step particle-coating method, pyrochlore-free Pb(Mg 1/3 Nb 2/3 )O 3 (PMN) powders have been successfully synthesized by a single calcination step at a relatively lower calcined temperature of 8501C. The XRD and EDS results confirmed that the Mg-citric acid polymeric complex coatings effectively prevent direct contact between PbO and Nb 2 O 5 and thus avoid the formation of pyrochlore phase. The coated powders were calcined directly without the ball-milling procedure at 8501C. The pyrochlore-free PMN powders obtained showed uniform and even grain size. The results showed that this method is an attractive method for the synthesis of PMN-based composite powders.

Synthesis and thermochemistry of relaxor ferroelectrics in the lead magnesium niobate–lead titanate (PMN–PT) solid solutions series

“…22,23 Another alternative to avoid pyrochlore is tailoring synthesis methods to change the chemical characteristics of the reactants. Xu et al 24 developed a particle coating method in which a magnesium citrate polymeric complex prevents direct contact between PbO and Nb 2 O 5 and thus avoids the formation of pyrochlore. Yu et al 25 synthesized PMN-PT perovskite single phase by introducing polyethylene glycol to a mixture of MgO, PbO, Nb 2 O 5 and TiO 2 .…”