Engineering Atomic Sites via Adjacent Dual‐Metal Sub‐Nanoclusters for Efficient Oxygen Reduction Reaction and Zn‐Air Battery

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2020-12, Vol.16 (48), p.e2004855-n/a
• Main Authors: Qi, Defeng, Liu, Yifan, Hu, Min, Peng, Xianyun, Qiu, Yuan, Zhang, Shusheng, Liu, Wei, Li, Hongyi, Hu, Guangzhi, Zhuo, Longchao, Qin, Yongji, He, Jia, Qi, Gaocan, Sun, Jiaqiang, Luo, Jun, Liu, Xijun
• Format: Article
• Language: English
• Subjects: air cathode; atomic clusters; bimetallic Cu‐Zn; Catalysts; Chemical synthesis; Fine structure; Metal air batteries; Nanoclusters; Nanotechnology; oxygen reduction reaction; Oxygen reduction reactions; Zinc; Zn‐air battery
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202004855

N‐coordinated transition‐metal materials are crucial alternatives to design cost‐effective, efficient, and highly durable catalysts for electrocatalytic oxygen reduction reaction. Herein, the synthesis of uniformly distributed Cu−Zn clusters on porous N‐doped carbon, which are accompanied by Cu/Zn‐Nx single sites, is demonstrated. X‐ray absorption fine structure tests reveal the co‐existence of M−N (M = Cu or Zn) and M−M bonds in the catalyst. The catalyst shows excellent oxygen reduction reaction (ORR) performance in an alkaline medium with a positive half‐wave potential of 0.884 V, a superior kinetic current density of 36.42 mA cm−2 at 0.85 V, and a Tafel slope of 45 mV dec−1, all of which are among the best‐reported results. Furthermore, when employed as an air cathode in Zn‐Air battery, it reveals a high open‐cycle potential of 1.444 V and a peak power density of 164.3 mW cm−2. Comprehensive experiments and theoretical calculations approved that the high activity of the catalyst can be attributed to the collaboration of the Cu/Zn‐N4 sites with CuZn moieties on N‐doped carbons. Cu−Zn clusters, accompanied by Cu and Zn single sites, are reasonably prepared on N‐doped carbon, which shows an outstanding oxygen reduction performance in an alkaline medium as well as high efficiency when assembled into a Zn‐air battery. Theoretical calculations reveal the interplay derived from Zn‐Nx, Cu‐Nx, and adjacent CuZn clusters are the driving force to their excellent electrocatalytic performance.