Firstly, the stability of the arsenicals adsorbed onto Phos and PhosO were studied using adsorption energy in water (Eads, Fig. ). To have a comparative perspective, the adsorption onto intrinsic phosphorene is contemplated. Neutral trivalent and pentavalent methylarsenicals show adsorption energies onto intrinsic phosphorene in the range of 0.35-0.68 eV, while anionic pentavalent methylarsenicals shows adsorption energies of up to 1.33