Structural modulation of ZIF-67-derived CoP/C catalysts and their enhanced hydrogen and oxygen evolution performance

The growing global demand for clean energy has underscored the need for efficient and stable non-precious metal electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in water splitting. In this study, ZIF-67 was employed as the precursor and red phosphorus (P) as the phosphorization agent. By precisely controlling the phosphorization temperature, CoP/C composite catalysts were successfully synthesized. Characterization through techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) demonstrated that the CoP/C-7 sample, prepared at 700℃, exhibited excellent crystallinity, a mesoporous structure, and uniform distribution of CoP nanoparticles on the carbon matrix. This unique structure enhanced both electron conductivity and catalytic activity. Electrochemical tests in 1 mol/L KOH solution revealed that CoP/C-7 achieved current densities of 10 mA·cm⁻² at overpotentials of 233.5 mV for HER and 337 mV for OER, accompanied by a low Tafel slope, indicating its superior electrocatalytic performance for both reactions. Furthermore, the catalyst displayed remarkable long-term stability with minimal degradation in performance. This study introduces an innovative approach for synthesizing MOF-derived catalysts and provides valuable insights into the development of efficient, non-precious metal electrocatalysts for renewable energy applications.