Always cubes: A comparative evaluation of gas phase synthesis methods and precursor selection for the production of MgO nanoparticles

MgO nanocubes are well-suited for the study of defects and interfaces inside metal oxide powders and ceramics. We evaluated the synthesis of MgO nanocubes via flame spray pyrolysis (FSP) and compared the structural and spectroscopic particle properties with materials obtained by chemical vapor synthesis (CVS). Characterization of the as-synthesized and vacuum annealed powder samples revealed slightly larger particle sizes for the FSP material that is absolutely comparable to CVS powders in terms of the particles structural definition, morphology and crystallinity. Moreover, optical absorption and photoluminescence emission studies show fingerprints, which are characteristic of MgO nanocrystals with a high abundance of grain corners, kinks and edges. The opportunity to synthesize MgO nanoparticles of high structural definition via FSP at significantly larger production rates and lower costs compared to CVS carries great potential to upscale powder production to generate MgO based functional oxide nanocomposites for ceramics and catalysis.