La28−xW4+xO54+3x/2 Powders Prepared by Spray Pyrolysis

Abstract

Here we report the first aqueous solution‐based synthesis route to lanthanum tungstate nanopowders (La28−xW4+xO54+3x/2). Lanthanum tungstate‐based materials have high proton conductivity at elevated temperatures making them interesting for several energy technology applications. The La28−xW4+xO54+3x/2 powders prepared by developing a new aqueous precursor solution have a narrow particle size distribution with an average grain size of 100 nm. Different pre‐consolidation conditions were studied to enhance powder performance. Dense, single phase materials with homogeneous microstructures with grain size ~4 μm were obtained using sintering temperatures at 1400°C in air. Changing the La/W‐ratio from 5.6 to 5.4 did not affect the densification rate, however, a slight increase in grain growth rate was observed.