Construction of ZIF-67/MIL-88(Fe, Ni) catalysts as a novel platform for efficient overall water splitting

Authors：Chen, Pinghua; Duan, Xueqing; Li, Guifang; Qiu, Xianhua; Wang, Shuai; Huang, Yiping; Stavitskaya, Anna; Jiang, Hualin^*

Source：International Journal of Hydrogen Energy, 2023, 48(20): 7170-7180.

DOI：10.1016/j.ijhydene.2022.11.080

• ZIF-67
• MIL-88(Fe Ni)
• Electrocatalysts
• Overall water splitting
• Composite

Constructing bifunctional non-precious metal electrocatalysts is necessary for effective overall water splitting (OWS), but challenging. Herein, a novel hybrid nanostructure of ZIF-67/MIL-88(Fe, Ni), denoted as Co-M-Fe/Ni(x) (x represents the mass of ZIF-67), was suc-cessfully synthesized by hydrothermal and in-situ growth method, and showed a highly efficient and stable bifunctionality of both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline electrolyte. The Co-M-Fe/Ni(150) exhibited excellent OER performance with a low overpotential of 269 mV and 149 mV @ 10 mA cm-2 for OER and HER in 1 mol L-1 KOH, respectively. With Co-M-Fe/Ni(150) as cathode and anode, the integrated OWS device had achieved low potential of 1.52 V @ 10 mA cm-2, exhibiting its excellent performance of OWS. Based on the results of experiments, ZIF-67 and MIL-88(Fe, Ni), as metal-organic frameworks (MOFs), which have a large specific surface area, uniform distribution of porous structures facilitates charge transmission, promoting the penetra-tion of electrolytes, and improves electron transfer rate. The mechanism of the superior electrocatalytic performance of Co-M-Fe/Ni(150) may be attributed to the synergy of ZIF-67 and MIL-88(Fe, Ni). This work provides guidance for the rational design or optimization of non-noble composites for energy conversion.

• Institution
  南昌航空大学