Influence of vacancy defects on 2D BeN<sub>4</sub> monolayer for NH<sub>3</sub> adsorption: a density functional theory investigation
Seetha Lakshmy, Gopal Sanyal, Nandakumar Kalarikkal, Brahmananda Chakraborty
Abstract
Abstract Two-dimensional materials have attracted a great deal of interest in developing nanodevices for gas-sensing applications over the years. The 2D BeN 4 monolayer, a recently synthesized single-layered Dirac semimetal, has the potential to function as a gas sensor. This study analyzes the NH 3 sensing capacity of the pristine and vacancy-induced BeN 4 monolayers using first-principles density functional theory (DFT) calculations. As per the results, the NH 3 molecule is physisorbed on the pristine BeN 4 via weak Van der Waals interaction with a poor adsorption energy of −0.41 eV and negligible charge transfer. Introducing Be vacancy in BeN 4 increased the NH 3 adsorption energy to −0.83 eV due to the improved charge transfer (0.044 e) from the defective monolayer to the NH 3 molecule. The structural stability, sufficient recovery time (74 s) at room temperature, and superior work function sensitivity promise the potential application of defective BeN 4 as an NH 3 sensor. This research will be a theoretical groundwork for creating innovative BeN 4 -based NH 3 gas sensors.