Friday, 4 May 2018

A universal principle for a rational design of single-atom electrocatalysts

Source: Nature Catalysis (2018); doi:10.1038/s41929-018-0063-z; Received: 21 November 2017, Accepted: 27 March 2018, Published:
30 April 2018

Authors: Haoxiang Xu, Daojian Cheng, Dapeng Cao & Xiao Cheng Zeng

- Haoxiang Xu, Daojian Cheng, Dapeng Cao & Xiao Cheng Zeng
Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, China
- Daojian Cheng & Dapeng Cao
State Key Laboratory of Organic-Inorganic Composites, Beijing Key Laboratory of Energy Environmental Catalysis, Beijing University of Chemical Technology, Beijing, China
- Xiao Cheng Zeng
Department of Chemistry, Department of Chemical & Biomolecular Engineering, and Department of Mechanical & Materials Engineering, University of Nebraska, Lincoln, NE, USA

Abstract

Developing highly active single-atom catalysts for electrochemical reactions is a key to future renewable energy technology. Here we present a universal design principle to evaluate the activity of graphene-based single-atom catalysts towards the oxygen reduction, oxygen evolution and hydrogen evolution reactions. Our results indicate that the catalytic activity of single-atom catalysts is highly correlated with the local environment of the metal centre, namely its coordination number and electronegativity and the electronegativity of the nearest neighbour atoms, validated by available experimental data. More importantly, we reveal that this design principle can be extended to metal–macrocycle complexes. The principle not only offers a strategy to design highly active nonprecious metal single-atom catalysts with specific active centres, for example, Fe-pyridine/pyrrole-N4 for the oxygen reduction reaction; Co-pyrrole-N4 for the oxygen evolution reaction; and Mn-pyrrole-N4 for the hydrogen evolution reaction to replace precious Pt/Ir/Ru-based catalysts, but also suggests that macrocyclic metal complexes could be used as an alternative to graphene-based single-atom catalysts.

Read more at: https://www.nature.com/articles/s41929-018-0063-z#author-information

Fig. 1: Schematic of a single TM atom supported on graphene with different coordination environments.