Interactions of gas molecules with monolayer MoSe₂: A first principle study

We present a first principle study of interaction of toxic gas molecules (NO, NO₂ and SO₂) with monolayer MoSe₂. The predicted order of sensitivity of gas molecule is NO₂ > SO₂ > NO. Adsorbed molecules strongly influence the electronic behaviour of monolayer MoSe₂ by inducing impurity levels in the vicinity of Fermi energy. NO and SO₂ is found to induce p-type doping effect while semiconductor to metallic transitions occur on NO₂ adsorption. Our findings may guide the experimentalist for fabricating sensor devices based on MoSe₂ monolayer.