Proton Capture Strategy for Enhancing Electrochemical CO2 Reduction on Atomically Dispersed Metal–Nitrogen Active Sites**

Xinyue Wang,Liming Dai,Chung‐Li Dong,Siyu Yao,Bin Yang,Zhongjian Li,Lecheng Lei,Xiahan Sang,Ling Shuai,Ming Qiu,Yang Hou,Jianguo Lu

doi:10.1002/ange.202100011

Abstract

AbstractElectrocatalysts play a key role in accelerating the sluggish electrochemical CO2 reduction (ECR) involving multi‐electron and proton transfer. We now develop a proton capture strategy by accelerating the water dissociation reaction catalyzed by transition‐metal nanoparticles (NPs) adjacent to atomically dispersed and nitrogen‐coordinated single nickel (Ni−Nx) active sites to accelerate proton transfer to the latter for boosting the intermediate protonation step, and thus the whole ECR process. Aberration‐corrected scanning transmission electron microscopy, X‐ray absorption spectroscopy, and calculations reveal that the Ni NPs accelerate the adsorbed H (Had) generation and transfer to the adjacent Ni−Nx sites for boosting the intermediate protonation and the overall ECR processes. This proton capture strategy is universal to design and prepare for various high‐performance catalysts for diverse electrochemical reactions even beyond ECR.

Highlights

Electrochemical CO2 reduction (ECR) has been widely studied as a way of energy storage to tackle the current energy and environmental challenges.[1]
As a typical product that can be highly energy-efficiently generated through a two-electron transfer process, CO gas from ECR is very attractive for a wide range of industrial applications because CO can be readily used as an essential feedstock for Fischer-Tropsch synthesis.[2]
It has been previously proved that the delocalization of unpaired electron in 3d orbital allowing for efficient charge transfer from TM center to CO2 molecule was beneficial to the activation of adsorbed CO2 species and responsible for the high intrinsic ECR activity of TM-NC electrocatalysts.[3b]. TM-NC catalysts still suffer from inefficient and sluggish reaction kinetics associated with the proton-coupled electron transfer process of CO2 to CO,[4] which seriously hinder their practical applications

Summary

RESEARCH ARTICLE

Xinyue Wang,[a] Xiahan Sang,[c] Chung-Li Dong,[d] Siyu Yao,[a] Ling Shuai,[b] Jianguo Lu,[g] Bin Yang,[a,e] Zhongjian Li,[a,e] Lecheng Lei,[a,e] Ming Qiu,*[b] Liming Dai,*[f] and Yang Hou*[a,e]. Supporting information for this article is given via a link at the end of the document

Introduction

Partial density of states

NiN CM d state of NiN CM

Microporous NCNTs

Ni g

Reaction coordinate c