Formation of droplets in a heterophasic amorphocrystalline nanopowder Bi2O3 produced by pulsed electron beam evaporation in vacuum

Abstract

Abstract In the present work, a mesoporous multiphase amorphous crystal nanopowder Bi2O3 with a specific surface area of up to 23 m2/g was produced by pulsed electron beam evaporation in vacuum. Influence of thermal annealing (200-500 °C) of powders in air is investigated. The formation of droplets with a size of 3-5 nm on the surface of all large nanoparticles constituting the framework 3D nanopowder agglomerates was found due to extrusion of liquid bismuth from the volume during cooling.