Electronic Properties and Electrocatalytic Water Splitting Activity for Precious-Metal-Adsorbed Silicene with Nonmetal Doping

Abstract

Since nonmetal (NM)-doped two-dimensional (2D) materials can effectively modulate their physical properties and chemical activities, they have received a lot of attention from researchers. Therefore, the stability, electronic properties, and electrocatalytic water splitting activity of precious-metal (PM)-adsorbed silicene doped with two NM atoms are investigated based on density functional theory (DFT) in this paper. The results show that NM doping can effectively improve the stability of PM-adsorbed silicene and exhibit rich electronic properties. Meanwhile, by comparing the free energies of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) intermediates of 15 more stable NM-doped systems, it can be concluded that the electrocatalytic water splitting activity of the NM-doped systems is more influenced by the temperature. Moreover, the Si-S2-Ir-doped system exhibits good HER performance when the temperature is 300 K, while the Si-N2-Pt-doped system shows excellent OER activity. Our theoretical study shows that NM doping can effectively promote the stability and electrocatalytic water splitting of PM-adsorbed silicene, which can help in the application of silicene in electrocatalytic water splitting.