Tuning the structural, electronic and adsorption properties of Au-embedded 2D WSe2 and Arsenene nanosheets: A DFT study.

• Au-adsorbed WSe 2 and Arsenene monolayers show great potential for application as gas sensors. • NO 2 molecule shows the strongest adsorption on the arsenene and WSe 2 monolayers. • The NO and NO 2 -adsorbed Au-arsenene monolayers exhibit metallic property. • CO, NO, and NO 2 adsorbed Au-WSe 2 monolayers represent semiconducting behavior. In this paper, we examined the adsorption of NO 2 , NO, and CO molecules on the Au-adsorbed WSe 2 and arsenene nanosheets using the density functional theory calculations. The adsorption of Au on the hollow sites of the nanosheets was considered. Au-embedded WSe 2 and arsenene nanosheets have higher sensitivity than the perfect ones for application as gas sensor for the detection of NO 2 , NO, and CO molecules. Based on our calculations, we found that Au-adsorbed arsenene and WSe 2 systems can be effectively applied for practical sensing purposes. We also found that Au-WSe 2 nanosheets strongly satisfy the requirements for toxic gas sensing due to their higher binding energies and consequently improved electronic structure and adsorption performance as compared to the Au-arsenene nanosheets. Our calculated results suggested that Au-arsenene and Au-WSe 2 systems are promising nanomaterials for future gas sensor systems. [ABSTRACT FROM AUTHOR]