A first-principles insight into Pd-doped MoSe2 monolayer: A toxic gas scavenger

Using first-principles theory, we investigate the Pd-doping effect on the geometric and electronic behaviors of MoSe₂ monolayer, and the adsorption behavior of Pd-MoSe₂ monolayer upon four toxic gases, namely NO, NO₂ SO₂ and H₂S. Desorption property of Pd-MoSe₂ monolayer upon four gases at diverse temperatures is analyzed as well to help explore its potential application. For Pd dopant adsorption onto MoSe₂ monolayer, somewhat n-type doping is determined, which accounts for the increased conductivity for intrinsic MoSe₂ monolayer. The strong adsorption ability and poor desorption performance of Pd-MoSe₂ monolayer upon four gases indicate its large potential as gas scavenger to remove these toxic gases from their surroundings. Moreover, it could be explored as a gas sensor for detection of NO, NO₂ and H₂S as well, given the obvious change in conductivity after gas adsorption based on band structure analysis. Our calculations would be beneficial to understand the TM doping effect on intrinsic MoSe₂ monolayer and to provide a first insight into the potential application as gas sensor or sweeper for Pd-MoSe₂ monolayer.