J. Mater. Sci. Technol. ›› 2023, Vol. 137: 184-192.DOI: 10.1016/j.jmst.2022.07.044

• Research Article • Previous Articles     Next Articles

Engineering the interface of porous CoMoO3 nanosheets with Co3Mo nanoparticles for high-performance electrochemical overall water splitting

Haibin Ma1, Xuejing Yang1, Zhili Wang*, Qing Jiang*   

  1. Key Laboratory of Automobile Materials, Ministry of Education, and School of Materials Science and Engineering, Jilin University, Changchun 130022, China
  • Received:2022-06-13 Revised:2022-07-26 Accepted:2022-07-27 Published:2023-02-20 Online:2023-02-15
  • Contact: *E-mail addresses: zhiliwang@jlu.edu.cn (Z. Wang), jiangq@jlu.edu.cn (Q. Jiang).
  • About author:1These authors contributed equally to this work.

Abstract: The design of high-performance electrocatalysts for alkaline water splitting is of significant importance for the development of a sustainable hydrogen economy. Herein, heterostructured Co3Mo nanoparticles/porous CoMoO3 nanosheets (Co3Mo/CoMoO3 NPSs) were constructed for alkaline water splitting by annealing CoMoOx nanosheets under controlled atmospheres. Thanks to its interfacial electronic structure and increased electrochemical active area, Co3Mo/CoMoO3 NPSs exhibit impressive hydrogen evolution reaction (HER) activity with an overpotential of 334 mV at 1000 mA cm-2 and a Tafel slope of 46.4 mV per decade in 1.0 M KOH, which outperforms Pt/C catalyst (621 mV and 74.7 mV per decade). Density functional theory calculations illustrate the electron transfer from Co3Mo to CoMoO3 at the interfaces, where electron accumulation on CoMoO3 favors the dissociation of H2O molecule, and electron-deficient Co atoms in Co3Mo have optimized H* absorption energy for HER. The Co3Mo/CoMoO3 NPSs also exhibit higher oxygen evolution reaction activity than the RuO2 catalyst. Moreover, the water electrolyzer using Co3Mo/CoMoO3 NPSs as both cathode and anode only requires 1.59 V to deliver a current density of 100 mA cm-2 in 1.0 M KOH, which outperforms benchmark Pt/C || RuO2 electrodes couple with 1.69 V to reach the same current density, providing great potential for large-scale applications.

Key words: Interface engineering, Heterostructures, Interfacial electronic structure, Hydrogen evolution reaction, Overall water splitting