Bandgap evolution of Mg₃N₂ under pressure: Experimental and theoretical studies

Abstract

Wide bandgap semiconductors are crucially significant for optoelectronic and thermoelectric device applications. Metal nitride is a class of semiconductor material with great potential. Under high pressure, the bandgap of magnesium nitride was predicted to grow. Raman spectra, UV-Vis absorption spectra, and first-principles calculations were employed in this study to analyze the bandgap evolution of Mg3N2. The widening of the bandgap has been first detected experimentally, with the gap increasing from 2.05 eV at 3 GPa to 2.88 eV at 47 GPa. According to the calculation results, the enhanced covalent component is responsible for the bandgap widening.