Properties of compacts of barium fluoride nanopowder produced by pulsed electron beam evaporation

Abstract

Abstract Mesoporous crystalline BaF 2 nanopowder with a specific surface area of up to 34.8 m 2 /g was produced by a pulsed electron beam through the evaporation of targets of micro-sized BaF 2 powder with optical purity ( S red = 0.38 m 2 /g). The texture and thermal features of the BaF 2 nanopowder (before and after annealing in air at a temperature of 200 °C) and some properties of compacts made of the BaF 2 nanopowder by magnetic-pulse compaction and static pressing were studied. Glassy, opaque, and black compacts, which are promising materials for use as scintillators and dosimeters, were produced by magnetic-pulse compaction in a vacuum at a temperature of about 425 °C. It was found that heating up to 425 °C is sufficient for removing defects in nanopowders. The effect of pressing methods on the pulsed cathodoluminescence and photoluminescence spectra of the compacts was studied. Luminescent properties were found to depend on pressing technology. It was also determined that surface color centers, the number of which decreases during heating, are responsible for the pulsed cathodoluminescence band near ∼560 nm.