A first-principles study on the adsorption properties of phosphorene oxide for pollutant removal from water

• Published in: Journal of molecular liquids 2022-07, Vol.357, p.119103, Article 119103
• Main Authors: Cortés-Arriagada, Diego, Barria, Natacha, Ortega, Daniela E., Araya-Durán, Ingrid, Belén Camarada, María
• Format: Article
• Language: English
• Subjects: Environmental pollution; Nanotechnology; Surface science; Water pollution
• ISSN: 0167-7322; 1873-3166
• DOI: 10.1016/j.molliq.2022.119103

[Display omitted] •PhosO promoted adsorption of emerging contaminants by inner-surface adsorption.•The adsorption strength is retained under aqueous environments.•A contribution of dispersion/electrostatic forces explains the adsorption efficiency.•Oxidation promotes low pollutant mobility and high stability at room temperature.•Effects in the substrate electronic properties provide a framework for sensing. Phosphorene-based materials have emerged as useful platforms for new technological applications, including their potential implementation in the solid-phase extraction of pollutants. In this study, we implemented a first-principles study to characterize the interactions between water-soluble pollutants and phosphorene oxide (PhosO) at the microscopic level, providing useful mechanistic insights into the role of phosphorene oxidation in its adsorption/removal ability. Continuum/explicit solvent effects were considered to explain the solvent role, and the ALMO-EDA method characterizes the intermolecular forces. Our results show that PhosO significantly adsorbs pollutants on its surface by inner surface adsorption, even under aqueous environments, and provides remarkable adsorption stability for a wide family of water-soluble emerging contaminants (pharmaceuticals, endocrine disruptors, flame retardants, and industrial chemicals) with adsorption energies of 0.53 to 1.17 eV. The stabilizing energy in solution is driven by a balanced contribution of dispersion and electrostatic driving forces (up to 83% of the stabilizing energy), overcompensating all the destabilizing effects from the solvation process and Pauli repulsion. Furthermore, PhosO promotes low pollutant mobility from its surface under water molecules, which are not competitive factors in the adsorption process. In addition, simulations under dynamic conditions show that the electrostatic/dispersion governed mechanism remains stable at room conditions for real-life applications (300 K, 1 atm). Finally, a bandgap increase of 0.73 eV is noted in PhosO upon pollutant adsorption, giving a suitable framework for further sensing applications of contaminants by increasing the metallic character of PhosO. These results expand the understanding of the role of phosphorene oxidation for its use as a removal platform in water treatment technologies.