In-situ fabrication of MOF@CoP hybrid bifunctional electrocatalytic nanofilm on carbon fibrous membrane for efficient overall water splitting

Construction of metal-organic framework@cobalt phosphide (MOF@CoP) hybrid materials with enriched structures and excellent synergistic electrocatalytic properties for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is still highly desirable. Herein, a new series of Co-MOF@CoP hybrid nanofilms with controllable content ratio are successfully fabricated on carbon fibrous membrane (CFM) for electrocatalytic overall water splitting. Multiple characterization techniques verify the partial phosphorization of Co-MOF to CoP for an unique hybrid structure, where the remained Co-MOF with an interconnected porous structure not only provides efficient and fast channels for reactants/products transportation but also stabilizes the resulted CoP species in Co-MOF with an intimate interaction. As a result, the optimized Co-MOF@CoP@CFM catalyst exhibits remarkable electrocatalytic activity both for HER and OER, which only requires a voltage of 1.58 V to achieve the current density of 10 mA cm−2 for the overall water splitting. The results provide some inspiration for the design and construction of advanced porous nanofilm catalysts.