Efficient preparation and characterization of Zn₃N₂ powder

Zn₃N₂ powders were prepared by the high-temperature direct nitriding method using metallic zinc powder as the raw material, ammonia gas as the nitrogen source, and glycerol as the additive. The effects of glycerol content, reaction temperature, and reaction time on the mass fraction of Zn₃N₂ in the products were studied. The phase composition, microstructure, elemental distribution, and the sample surface chemical state of the products were analyzed by X-ray diffractometer, scanning electron microscope, X-ray energy dispersive spectrometer, and X-ray photoelectron spectroscopy. In the results, the glycerol bonds within the molecule begin to break after heating, which makes the reducing substances reduce ZnO on the surface of zinc powders, lowering the content of ZnO. This is conducive to the reaction between Zn and NH₃ in the later stage, increasing the content of Zn₃N₂ in the products and improving the dispersibility of Zn₃N₂ powders. When the ratio of glycerol to zinc powder (volume/mass, mL/g) is 0.20, after heating at 600 ℃ for 3 h, the Zn₃N₂ powders with mass fraction of of 95.72% can be prepared, and the optical band gap of the obtained Zn₃N₂ powders is 2.60 eV.