The potential of stanene with transition metal adsorbed as a promising gas sensor: A first-principles study

Abstract

In this paper, the structural, electronic and magnetic properties of TM (TM = Zr, Mo, Nb) absorbed stanene with the adsorption of toxic gas molecules (CO, CO2, NO, NO2, SO2, and NH3) have been investigated using the first-principles calculations. The calculated results show that the adsorption of TM induces the magnetic properties of stanene, and the adsorption of gas molecule on TM-stanene can tune the magnetic moment. For the adsorption of CO, CO2 and NH3 on Nb-stanene, it can be clearly seen that the whole system represent half-metallic character. When six gas molecules are adsorbed on the Mo-stanene system, it is found that they all exhibit semiconducting properties. However, for the adsorption of NO and NO2 on the Zr-stanene system, it is shown that the whole system appears the transition from half-metallic character to metallic character. At the same time, it can be seen that the adsorption energy of TM-stanene with gas molecules adsorbed have increased by 3 ~ 5 times compared with that of pristine stanene monolayer, and the charge transfer have also significantly increased by 10 times. It indicates that TM-stanene with gas molecules adsorbed exhibit strong interactions, especially in the Zr-stanene system. Therefore, the TM-stanene is more suitable for gas molecules detection compared with the pristine stanene, and the calculated results suggest Zr-stanene is potential for gas sensing. This paper is expected to provide theoretical guidance for the design of toxic gas sensors.