Atomically Dispersed Pentacoordinated‐Zirconium Catalyst with Axial Oxygen Ligand for Oxygen Reduction Reaction

• Published in: Angewandte Chemie Vol. 134; no. 36
• Main Authors: Wang, Xia, An, Yun, Liu, Lifeng, Fang, Lingzhe, Liu, Yannan, Zhang, Jiaxu, Qi, Haoyuan, Heine, Thomas, Li, Tao, Kuc, Agnieszka, Yu, Minghao, Feng, Xinliang
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 05.09.2022
• Subjects: Catalysts; Chemical reduction; Chemistry; Durability; Heavy metals; High Single-Atom Loading; Intermediates; Ligands; Metal air batteries; Oxygen; Oxygen Reduction Reaction; Oxygen reduction reactions; Pentacoordinated Configuration; Single atom catalysts; Zinc-Air Battery; Zinc-oxygen batteries; Zirconium
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.202209746

Single‐atom catalysts (SACs), as promising alternatives to Pt‐based catalysts, suffer from the limited choice of center metals and low single‐atom loading. Here, we report a pentacoordinated Zr‐based SAC with nontrivial axial O ligands (denoted O−Zr−N−C) for oxygen reduction reaction (ORR). The O ligand downshifts the d‐band center of Zr and confers Zr sites with stable local structure and proper adsorption capability for intermediates. Consequently, the ORR performance of O−Zr−N−C prominently surpasses that of commercial Pt/C, achieving a half‐wave potential of 0.91 V vs. reversible hydrogen electrode and outstanding durability (92 % current retention after 130‐hour operation). Moreover, the Zr site shows good resistance towards aggregation, enabling the synthesis of Zr‐based SAC with high loading (9.1 wt%). With the high‐loading catalyst, the zinc‐air battery (ZAB) delivers a record‐high power density of 324 mW cm−2 among those of SAC‐based ZABs. The first Zr‐based single‐atom catalyst with a stable pentacoordinated structure and high single‐atom Zr loading is discovered. With the high‐loading catalyst, the assembled zinc–air battery delivers a record‐high power density among those of single‐atom catalyst‐based zinc–air batteries.