Achieving tunable adsorption selectivity and sensitivity of boridenes for gas detection by surface O-termination engineering.

This study utilizes density functional theory (DFT) to explore the potential of using boridenes as gas-sensing materials for common organic and inorganic gases, including CH, CH, CH, CFN, CHO, CH, CO, CO, H, HO, N, NO, NO, O, SF and SO. The adsorption atomic configurations and adsorption energies are calculated for all gas species in the MoB-MoBO series, elucidating the change in the adsorption mechanism from chemisorption for the bare MoB monolayer to physisorption in the case of the MoBO monolayer and also manifesting the significance of O-terminations on the adsorption properties of boridenes for the considered gas species. In addition, the gas-sensing parameters, including recovery time, sensitivity and selectivity, are evaluated for MoB and MoBO monolayers to demonstrate the tunable sensing performance of boridenes for target gas species by tailoring the surface functional groups. The results reveal that the bare MoB shows promising reusability and selectivity for detecting insulating gases (SF and CFN) and their dissociated products (SO and CO), while the presence of O-terminations greatly improves the recovery time (10 s), sensitivity (100.0%) and selectivity (exclusive NO adsorption) of sensing NO pollutants in the air for the MoBO monolayer. Overall, this work is expected to benefit the research and development of gas-sensing materials based on boridenes for various application scenarios in the future experimental study.