Alkaline earth metal-doped monolayer AlN: A DFT study of photocatalytic and magnetic properties

The presence of the unintentional impurities C and O has been reported in the preparation of two-dimensional AlN using metal organic vapor phase epitaxy or molecular beam epitaxy under vacuum conditions, whereas the occurrence of VAl is inevitable. Thus, the photocatalytic and magnetic properties of monolayer AlN containing VAl, an unintentional impurity (C/O), and Be/Mg/Ca impurity are studied by using the GGA + U method based on density functional theory. Results indicate that the magnetic moment of Al34OiBeN36 is 2 mu B, making it relatively suitable for spintronic devices. The Al34OiCaN36 system has the best visible-light absorption, relatively appropriate band-edge position, and relatively easy carrier separation and migration. Therefore, this system is suitable to be used as a photocatalyst for water decomposition. The results of this study will facilitate the preparation of AlN monolayers and provide insights into their potential applications in the field of spintronics and photocatalysis.