Borophene Nanoribbons via Strain Engineering for the Hydrogen Evolution Reaction: A First-Principles Study
Xiaoyuan Wang, Rongyao Wu, Pengfei Tian, Yabin Yan, Yang Gao, Fuzhen Xuan
Abstract
Borophene has been reported to be a promising catalyst for the hydrogen evolution reaction (HER) in recent research studies; however, as a new-born two-dimensional material, there are a lot of issues still remain to be explored. In the present study, we explore the catalytic performance of borophene nanoribbons (BNRs) using first-principles calculations. Our calculations show that BNRs can be highly active edge-dependent catalysts for the hydrogen evolution reaction. The effects of the nanoribbon width and strain engineering on the catalytic performance of BNRs are further studied, and it was found that the width has no effect on the catalytic activity of armchair BNRs (ABNRs). On the other hand, the strain engineering is an effective method to significantly improve the catalytic activity of ABNRs. A Gibbs free energy of ΔGH ≈ 0 is achieved at a critical compressive strain of εC = −2%, suggesting that the ABNRs can be a catalyst for an ultrafast HER through the modulation of strain engineering. In addition, the projected B-2pz densities of states of ABNRs with different applied strains are analyzed to deeply understand the mechanism of strain engineering and the extra π bonds of edge reconstruction, which are modulated by strain-induced charge delocalization. The current study gives some critical insights into the catalytic activity of BNRs for the hydrogen evolution reaction.