Controlled formation of barium fluoride nanocrystals by electric-assisted phase separation and precipitation

Abstract

This work demonstrated that barium fluoride (BaF₂) nanocrystals can be controllably formed by an electric-assisted phase separation and precipitation method, EAPSP, in a water/ethanol mixture. Experimentally, we employed an electrostatic generator to provide various voltages to reduce the surface tension of a water/ethanol mixture to cause rapid phase separation after which BaF₂ nanocrystals formed and precipitated under control. Results showed that the average diameter of the formed BaF₂ nanocrystals was reduced with the voltage increase, e.g. the 0 V sample at about 70 nm in diameter, the 500 V sample at 50 nm in diameter and the 1000 V sample at 30 nm in diameter. The conductivity of these nanocrystals was found to increase with the decrease in size.