Chinese Journal of Catalysis ›› 2022, Vol. 43 ›› Issue (7): 1955-1962.DOI: 10.1016/S1872-2067(21)64035-4

• Articles • Previous Articles    

Ammonium cobalt phosphate with asymmetric coordination sites for enhanced electrocatalytic water oxidation

Jing Qia, Mingxing Chena, Wei Zhangb,*(), Rui Caob,#()   

  1. aSchool of Materials Science and Engineering, Henan Normal University, Xinxiang 453007, Henan, China
    bKey Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an 710119, Shaanxi, China
  • Received:2021-12-19 Accepted:2022-01-20 Online:2022-07-18 Published:2022-05-20
  • Contact: Wei Zhang, Rui Cao
  • Supported by:
    Natural Science Foundation of Henan Province(212300410183);National Natural Science Foundation of China(21872092);National Natural Science Foundation of China(21773146)


Cobalt-based materials have been considered as promising candidates to electrocatalyze water oxidation. However, the structure-performance correlation remains largely elusive, due to the complex material structures and diverse performance-influencing factors in those Co-based catalysts. In this work, we designed two cobalt phosphates with distinct Co symmetry to explore the effect of coordination symmetry on electrocatalytic water oxidation. The two analogues have similar morphology, Co valence and 6-coordinated Co octahedron, but with different coordination symmetry. In contrast to symmetric Co3(PO4)2·8H2O, asymmetric NH4CoPO4·H2O exhibited enhanced electrocatalytic water oxidation activity in a neutral aqueous solution. It is proven that, by experimental and theoretical studies, the asymmetric Co coordination sites can facilitate the surface reconstruction under anodic polarization to boost the electrocatalysis. Based on this contrastive platform with distinct symmetry differences, the preferred configuration in cobalt-oxygen octahedrons for water oxidation has been straightforwardly assigned.

Key words: Ammonium cobalt phosphate, Coordination symmetry, Surface reconstruction, Electrocatalysis, Oxygen evolution reaction