Preparation and Catalytic Performance of Ti/CoO@ZIF-67 Composite Electrode

Abstract

While cobalt oxides (CoO, Co₃O₄) have attracted considerable interest in photoelectrocatalysis (PEC), supercapacitors, and lithium-ion batteries due to their inherent three-dimensional electronic structure. Herein, CoO nanowires were synthesized by one-step hydrothermal method, and then ZIF-67 was generated in situ on CoO nanowires by simple impregnation method. Finally, Ti/CoO@ZIF-67 composite electrode was synthesized. In order to find the PEC electrode with the best performance, we optimized the experimental system by adjusting the amount of organic ligand (0.01 mol, 0.015 mol, 0.02 mol, 0.025 mol). The PEC activity of Ti/CoO@ZIF-67 electrode was studied by electrochemical properties and degradation efficiency of Ti/CoO@ZIF-67 electrode for active brilliant blue (KN-R). The results show that the Ti/CoO@ZIF-67–0.02 electrode exhibits the largest specific surface area, the smallest charge radius, the fastest charge mass transfer rate and the highest PEC degradation efficiency for KN-R. The composite electrode with different amount of organic ligand showed higher degradation efficiency than the single component electrode. This is due to the staggered band structure of CoO and ZIF-67, which accelerates the effective separation of photogenerated electrons and holes on the surface of the electrode, and improves the mineralization effect of the composite electrode on organic polymer materials. This study provides an application strategy for the construction of composite heterojunction materials.