Production of nanopowders of bismuth oxide doped with silver by pulsed electron beam evaporation in vacuum

Abstract

Various bismuth containing compounds are promising in many applications, including for creating photocatalysts based on them using a visible range of light. However, strong polymorphism (9 polymophic phases of Bi2O3), thermal instability and changes in the properties of bismuth oxide during long-term storage significantly complicate work with it. One way to increase stability and improve photocatalytic properties is by doping Bi2O3 with various metals. Ag doped Bi2O3 nanoparticles (NPs) are typically produced using chemical techniques often associated with the presence of toxic chemicals. The present paper used an environmentally friendly method of producing NPs using the method of pulsed electron beam evaporation in vacuum. The evaporation target was obtained by solid phase synthesis in an electric furnace on air using silver nitrate additives (1 and 5 wt.%). Textural, thermal and magnetic properties of the obtained NPs have been studied. Was found that the Ag-Bi2O3 NPs have a specific surface area (SSA) of 23.7 m2/g, which was almost 2 times bigger than the SSA of the pure Bi2O3 (13.2 m2/g) obtained previously. The thermal stability of the Ag-doped Bi2O3 samples was maintained to the temperature 350°C. While further heating on air took place the phase transition β → α