Zeolite Imidazole Framework-Derived Hollow Nickel-Cobalt Layered Double Hydroxide Intercalated with Metalloporphyrin...

The design of highly efficient, stable, and nonprecious-metal-based electrocatalysts for the oxygen evolution reaction (OER) has been a major research topic in the field of hydrogen production from electrolytic water splitting. In this work, a novel hierarchical hollow NiCo layered double hydroxide (NiCo LDH) with Cu-TCPP (TCPP = tetrakis(4-carboxyphenyl)-porphyrin) intercalation (denoted as X-CT/LR, where X is the amount of Cu-TCPP addition) was successfully fabricated by using zeolite imidazole framework-67 (ZIF-67) as a template. Among them, 1-CT/LR has superior OER activity and stability, requiring only a low overpotential of 204 mV to reach a current density of 10 mA/cm². The experimental results show that the introduced Cu-TCPP, in addition to being an active center itself, also acts as an electron transfer medium in the interlayer to enhance the conductivity of the material. Meanwhile, the hierarchical hollow structure and interlayer domain-limiting effect of NiCo LDH also ensure the dispersion and stabilization of Cu-TCPP, which is favorable to give full play to the synergistic catalytic effect of the two components. This work provides a facile strategy to obtain a nonprecious-metal-based OER electrocatalyst for water splitting.