J. Mater. Sci. Technol. ›› 2023, Vol. 164: 240-245.DOI: 10.1016/j.jmst.2023.04.024

• Letter • Previous Articles     Next Articles

Metal-organic framework-derived CoP2@N-doped carbon hollow spheres for efficient oxygen evolution reaction

Wei Zhanga, Jiangshui Luob,*, Xuan Zhanga,c,*, Wei Guoa, Ning Hana,*, Sijie Xiea,*, Zhenyu Zhoua, Zahid Anwera, Zhenhong Xuea, Jan Fransaera,*   

  1. aDepartment of Materials Engineering, KU Leuven, Leuven 3001, Belgium
    bLab of Electrolytes and Phase Change Materials, College of Materials Science and Engineering, Sichuan University, Chengdu 610065, China
    cZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 311215, China
  • Revised:2023-03-24 Published:2023-11-20 Online:2023-11-15
  • Contact: *E-mail addresses: Jiangshui.Luo@scu.edu.cn (J. Luo), xuan.zhang@kuleuven.be (X. Zhang), jan.fransaer@kuleuven.be (J. Fransaer)

Abstract: Developing a highly efficient and low-cost electrocatalyst is an important route to overcome the sluggish kinetics of the oxygen-evolution-reaction (OER). In this work, a series of hollow CoP2@N-doped carbon spheres are synthesized by a pyrolysis-phosphidation method. These hollow spheres are evaluated as electrocatalysts for the OER. Benefiting from the synergistic effects between highly active CoP2 and N-doped carbon (NC), the CoP2@NC-700H (pyrolyzed at 700 °C) exhibits outstanding electrocatalytic performances. The as-prepared hollow CoP2@NC-700 spheres tested on nickel foam have an onset potential of 1.36 V and reached a current density of 100 mA cm-2 at a potential of 1.42 V vs. RHE. It can attain a very high current density (600 mA cm-2) at a very low overpotential (265 mV). An alkaline water electrolyzer (Pt/C as cathode and hollow CoP2@NC-700 spheres as anode catalysts) exhibited excellent electrocatalytic activity and durability. As confirmed by experimental results, the CoP2@NC-700H works as a pre-catalyst for OER rather than as an active material.