Accelerated Reconstruction from Co-ZIF‑L to CoOOH via a Tailored Electronic Structure of Cobalt for Oxygen Evolution

• Published in: Industrial & engineering chemistry research 2024-05, Vol.63 (18), p.8142-8150
• Main Authors: Zhou, Qianqian, Qi, Zhijie, Yang, Xiaolong, Pan, Shugang, Hu, Yanling, Vasiliev, Alexander L., Wang, Xin, Fu, Yongsheng
• Format: Article
• Language: English
• Subjects: air; carbon; catalysts; cobalt; electrolysis; heat treatment; Kinetics, Catalysis, and Reaction Engineering; oxidation; oxygen production
• ISSN: 0888-5885; 1520-5045; 1520-5045
• DOI: 10.1021/acs.iecr.4c00491

The Oxygen Evolution Reaction (OER) encounters an insurmountable kinetic bottleneck in water electrolysis due to the complex four-electron transfer process, while modulating the oxidation states of active sites holds promise for enhancing the OER performance. Here, we successfully prepare cobalt-based zeolitic imidazolate framework Co-ZIF-L on carbon cloth with high-valence Co sites (O-ZIF-CC) through a facile oxidation strategy by heat treatment under an air atmosphere and achieve rapid reconstruction from Co-ZIF-L to CoOOH during OER. The O-ZIF-CC, as an active MOF-based catalyst, exhibits a low overpotential (283 mV at 10 mA cm–2). The excellent electrocatalytic activity of the O-ZIF-CC can be ascribed to the introduction of high-valence Co sites, facilitating reconstruction to generate CoOOH at low potentials. This work provides a feasible approach for understanding the optimization of the performance of MOF-based electrocatalysts through valence-state tuning.