Conductive bimetal organic framework nanorods decorated with highly dispersed Co3O4 nanoparticles as bi-functional electrocatalyst

The poor electronic conductivity and low intrinsic electrocatalytic activity of metal organic frameworks (MOFs) greatly limit their direct application in electrocatalytic reactions. Herein, we report a conductive two-dimensional pi-d conjugated Ni and Co bimetal organic framework (MOF)-NiCo-(2,3,6,7,10,11-hexaiminotriphenylene) (NiCo-HITP) nanorods decorated with highly dispersed Co3O4 nanoparticles (NPs) as a promising bi-functional electrocatalyst towards oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) through an effective and facile strategy by modifying the rod-shaped -Ni3HITP2 crystals using cobalt ions. The triggered electrocatalytic activity of the resulting MOF-based materials was achieved by increasing the electrical conductivity (7.23 S cm(-1)) originated from Ni(3)HITP(2 )substrate and also by creating the cooperative catalysis sites of Co-N (x) and Co3O4 NPs. Optimized syntheses show a promising ORR activity with a high half-wave potential (0.77 V) and also a significantly improved OER activity compared with pure Ni3HITP2 in alkaline electrolyte. Furthermore, a rechargeable Zn-air battery using the as-prepared material as air-cathode also shows a high power density (143.1 mW cm(-2))-even comparable to a commercial Pt/C-RuO2-based battery. This methodology offers a new prospect in the design and synthesis of non-carbonized MOF bi-functional electrocatalysts for efficient catalysis towards ORR and OER.

Automated summary

Poor electronic conductivity and low intrinsic electrocatalytic activity limit the direct application of metal organic frameworks (MOFs) in electrocatalysis. This study presents a conductive two-dimensional pi-d conjugated Ni and Co bimetal organic framework nanorod decorated with Co3O4 nanoparticles, which greatly enhances the electrocatalytic activity.