Programme

O.17 -- Oral, VCTP-51

Date: Tuesday, 4 August 2026

Time: 11:10 - 11:30

Exploring SnSe2 monolayer as a promising 2D material for the removal of heavy metals in wastewater

Nguyen Thanh Tien1, Truong Tuan Vu2, J. Guerrero-Sanchez3, and D. M. Hoat3*

1. College of Natural Sciences, Can Tho University, 3-2 Road, Can Tho City 900000, Vietnam 2. Institute of Theoretical and Applied Research, Duy Tan University, Ha Noi 100000, Viet Nam 3. Universidad Nacional Autonoma de Mexico, Centro de Nanociencias y Nanotecnologia, Apartado Postal 14, Ensenada, Baja California, Codigo Postal 22800, Mexico

Timely monitoring and removal of heavy metals from wastewater is actually critical considering that they cause severe issues for the environment and human health. In this work, SnSe2 monolayer is explored for the removal of heavy metals (HMs), including Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Iron (Fe), Mercury (Hg), and Lead (Pb), from wastwater. SnSe2 monolayer is a nonmagnetic semiconductor two-dimensional (2D) material with a band gap of 0.77 eV. Except for Cd and Hg metals that are physisorbed , other heavy metals are chemically adsorbed on SnSe2 monolayer with adsorption energies between -4.80 and -2.15 eV. It is also found that Cr and Fe adsorption induces signicant magnetism with overall magnetic moments of 3.53 and 2.22 B , respectively. In latter case, the half-metallicity is also obtained. Moreover, As, Cr, Cu, and Pb adsorption metallizes the monolayer, while the semiconductor nature is preserved after adsorbing Cd and Hg metals. The adsorption is considerably enhanced in aqueous conditions as a result of the metal stabilization induced by water molecules. The HM-Se chemical bond is predominantly ionic as consequence of the charge transfer from HM atoms to Se atom, which is conrmed by the Bader charge analysis and linear electron localization function. In explicit solvent, heavy metals lose larger charge quantities than in vacuum, strengthening the electrostatic interactions. Our study demonstrates promising adsorption performance of SnSe2 monolayer towards trapping heavy metals in both gas phase and in aqueous conditions, such that this 2D material can be introduced as a promising candidate for the removal of heavy metals from wastewater.

Presenter: Hoat Do Minh