Structural investigation and hydrogen storage of multilayer ZnO nanosheets

Abstract

The structures of ZnO graphene–like nanosheets (ZnOGLNSs) i.e. pyrene–like (PRL–ZnONS), coronene–like (CNL–ZnONS), circumcoronene–like (CCL–ZnONS), their multi–layers (PRL–ZnONS)n, (CNL–ZnONS)n, (CCL–ZnONS)n, (n= 2 to 4) and their non–terminated structures were obtained using B3LYP/LanL2DZ calculations. Hydrogenation energies of all studied ZnOGLNSs and their related energies are reported. Multilayerization of single–layer of non– and hydrogen–terminated PRL–ZnONS, CNL–ZnONS and CCL–ZnONS to afford their double–, triple– and quadruple–layers were studied and their binding energies were obtained. Adsorption configurations of NH₃ and H₂O on single–, double–, triple– and quadruple–layer CNL–ZnOGLNSs and their adsorption energies were obtained. Adsorption energies of CNL–ZnOGLNS and its multi–layers species are within the range of –28.25 to –21.52 kcal/mol for NH₃ and –40.18 to –12.03 kcal/mol for H₂O, respectively. Energy gaps, chemical indices of CNL–ZnOGLNS and its multi–layers species are reported.