Iron‐Cobalt‐Cerium Multimetallic Oxides Derived from Prussian Blue Precursors: Enhanced Oxygen Evolution Electrocatalysis

• Published in: ChemPlusChem (Weinheim, Germany) Germany), 2023-02, Vol.88 (2), p.e202200422-n/a
• Main Authors: Wu, Yaqiong, Kong, Yuxuan, Du, Binjie, Liu, Tian, Ying, Shuanglu, Xiong, Dengke, Yi, Fei‐Yan
• Format: Article
• Language: English
• Subjects: electrocatalysis; multimetal oxides; oxygen evolution reaction; Prussian blue analogues; water splitting
• ISSN: 2192-6506; 2192-6506
• DOI: 10.1002/cplu.202200422

Exploring non‐precious metal‐based electrocatalysts is still challenging in 21st century. In this work, a series of hexagonal bipyramidal Ce‐based PBA materials as precursors with different Fe/Co metal ratios, namely as CeFexCo1−x‐PBA, are successfully constructed via co‐precipitation method and converted into corresponding metal oxides (denoted as FexCo1−xCeOy) via thermal treatment. Then, they as electrocatalysts realize highly efficient oxygen evolution reaction (OER). Especially, as‐synthesized Fe0.7Co0.3CeOy electrocatalyst shows very low overpotentials of 320 mV at the current density of 10 mA cm−2 and the Tafel slop of 98.4 mV dec−1 in 1 M KOH with remarkable durability for 24 h, which was due to the synergistic effect of multi‐metal FeCoCe centers. Furthermore, a two‐electrode cell of Fe0.7Co0.3CeOy/NF||Pt/C/NF realizes outstanding overall water splitting with a voltage of only 1.71 V at 10 mA cm−2 and remarkable long‐term durability, that is even superior to benchmark IrO2/NF||Pt/C/NF counterpart. FexCo1−xCeOy nanomaterials with hexagonal bipyramidal morphology were successfully constructed and exhibit promising OER performance. Among them, Fe0.7Co0.3CeOy shows a low overpotential of 320 mV at 10 mA cm−2 with excellent cycling stability. A fabricated two‐electrode Fe0.7Co0.3CeOy/NF||Pt/C/NF cell only need 1.71 V for delivering current density of 10 mA cm−2 with great durability test of 24 h.