First, we analyzed some relevant electronic/chemical properties of the PhosO nanoadsorbents (Table ). The HOMO-LUMO energy difference (HL) of intrinsic phosphorene is 1.3 eV, denoting its semiconducting character in agreement with those reported from cluster models of phosphorene (∼1.5 eV) . eV) . Thus, the phosphorene oxidation (in O:P ratios from 1:8 to 1:1) almost does not affect the bandgap with respect to intrinsic phosphorene.