Defect and Doping Engineered Penta-graphene for Catalysis of Hydrogen Evolution Reaction

Jinbo Hao,Xinhui Zhang,Pengfei Lu,Xiaoguang Ma,Chunling Zhang,Long Li,Dan Liang,Feng Wei

doi:10.1186/s11671-021-03590-3

Abstract

Water electrolysis is a sustainable and clean method to produce hydrogen fuel via hydrogen evolution reaction (HER). Using stable, effective and low-cost electrocatalysts for HER to substitute expensive noble metals is highly desired. In this paper, by using first-principles calculation, we designed a defect and N-, S-, P-doped penta-graphene (PG) as a two-dimensional (2D) electrocatalyst for HER, and its stability, electronic properties and catalytic performance were investigated. The Gibbs free energy (ΔGH), which is the best descriptor for the HER, is calculated and optimized, the calculation results show that the ΔGH can be 0 eV with C2 vacancies and P doping at C1 active sites, which should be the optimal performance for a HER catalyst. Moreover, we reveal that the larger charge transfer from PG to H, the closer ΔGH is to zero according to the calculation of the electron charge density differences and Bader charges analysis. Ulteriorly, we demonstrated that the HER performance prefers the Volmer–Heyrovsky mechanism in this study.

Highlights

Because of the climate change and environmental pollution caused by fossil fuels usage, exploitation and utilization of clean and renewable energy are the mean way after nowadays [1–4]
Our calculations show that the pristine PG is found to be inert for the hydrogen evolution reaction (HER) with a relatively large The Gibbs free energy (ΔGH) of H, which means that hydrogen adsorption is difficult and HER is inhibited
We researched the possible active sites for doping and we investigated the active sites for C1 and C2 with N, S, P doping, respectively

Summary

Introduction

Because of the climate change and environmental pollution caused by fossil fuels usage, exploitation and utilization of clean and renewable energy are the mean way after nowadays [1–4]. For hydrogen evolution reaction (HER), platinum-based nanomaterials are considered as the best electrocatalysts because of a small Tafel slope, a low overpotential, a wide range of earth-abundant electrocatalysts have been studied and designed for HER [15–17]. Among these materials, two-dimensional (2D) nanomaterials provide new opportunities for HER because of the compelling structural and electronic properties. The TMDs HER catalysts have low overpotential and small Tafel slope, unusual electronic properties and high air stability, exhibit high HER performance, and different methods were taken for enhancing their catalytic performance [24, 25]. The graphene-based HER catalysts have attracted considerable attention and persistent studying because of their

Methods

Results

Conclusion