Rh-doped MoSe₂ as a toxic gas scavenger: a first-principles study

Using first-principles theory, we investigated the most stable configuration for the Rh dopant on a MoSe₂ monolayer, and the interaction of the Rh-doped MoSe₂ (Rh-MoSe₂) monolayer with four toxic gases (CO, NO, NO₂ and SO₂) to exploit the potential application of the Rh-MoS₂ monolayer as a gas sensor or adsorbent. Based on adsorption behavior comparison with other 2D adsorbents and desorption behavior analysis, we assume that the Rh-MoSe₂ monolayer is a desirable adsorbent for CO, NO and NO₂ storage or removal given the larger adsorption energy (E _ad) of -2.00, -2.56 and -1.88 eV, respectively, compared with other materials. In the meanwhile, the Rh-MoSe₂ monolayer is a good sensing material for SO₂ detection according to its desirable adsorption and desorption behaviors towards the target molecule. Our theoretical calculation would provide a first insight into the TM-doping effect on the structural and electronic properties of the MoSe₂ monolayer, and shed light on the application of Rh-MoSe₂ for the sensing or disposal of common toxic gases.