Lead adsorption onto Ni- and Pt-decorated nano γ-alumina: A first-principles study

Abstract

An efficient computational procedure was proposed to study the adsorption of leadonto two surface decorated alumina nanostructures using density functional theory (DFT) calculations. Notably, lead removal of abundantly available low-price decorated γ-alumina compounds was superior over previously studied functionalized 2D graphene nanosheets. The binding energy for adsorption of Pb on the most stable configuration of γ-alumina was −2.96 eV. Evaluation of adsorption energy demonstrated a noticeable increase in the binding energy of Ni- and Pt-decorated nano γ-alumina as −3.40 eV and −4.29 eV, respectively. Enhanced adsorption energy was taken as a sign of the chemisorption process of Pb on decorated γ-alumina surfaces via covalent bond formation. The use of the projected density of states (PDOS) plot elucidated strong hybridization of Pb 6p with Ni 3d orbitals and 5d orbital of Pt atoms. Moreover, the hybridization of Pb with aluminum 3p and oxygen 2p orbitals proved the strong interaction between Pb and Pt-decorated γ-alumina surface. The results of this investigation can shed some light on decontamination of wastewater applying Ni- and Pt-decorated γ-alumina surfaces. The The proposed approach can also be applied in design and manufacture of iefficient solid adsorbents for the removal of lead contaminations.