Bandgap evolution of Mg₃N₂ under pressure: Experimental and theoretical studies

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, ultra-violet-visible (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.