ZnCo₂O₄ nanoparticles derived from dual-metal-organic-frameworks embedded in Multiwalled Carbon Nanotubes: a favorable electrocatalyst for the water splitting

High-performance and cost effective electrocatalysts used for oxygen evolution reactions (OER) are indispensable in renewable-energy technologies. As an important 3D class of porous materials, Metal organic frameworks (MOF) with designable topological structures and compositions have been used as templates to obtain diverse functional materials. In this paper, ZnCo₂O₄@C-MWCNTs has been successfully synthesized by embedding dual-MOF into MWCNTs followed by calcinations under N₂ and air atmosphere in turn. The ZnCo₂O₄@C-MWCNTs hybrid exhibits enhanced OER performance in terms of an onset potential (1.45 V vs. RHE) and a low overpotential (327 mV) at 10 mA cm⁻². It is noteworthy that the potentials of ZnCo₂O₄@C-MWCNTs remain almost constant for 25 h in alkaline solution. Compared with many MOF derived matrix for OER applications, in-situ carbon formed during calcination process under N₂ atmosphere can not only improve the material's conductivity, but also prevent the agglomeration of active nanoparticles. The design concept of dual-MOFs-doped MWCNTs can be significantly expanded to fabricate other novel and stable catalysts for a wide range of applications.