Metal-organic framework derived heterostructured phosphide bifunctional electrocatalyst for efficient overall water splitting

Developing high active and stable cost-effective bifunctional electrocatalysts for overall water splitting to produce hydrogen is of vital significance in clean and sustainable energy development. This work has prepared a novel porous unreported MOF (Ni-DPT) as a precursor to successfully synthesize a non-noble bifunctional NiCoP/ Ni12P5@NF 12 P 5 @NF electrocatalyst through doping strategy and interface engineering. This catalyst is constructed by layered self-supporting arrays with heterojunction interface and rich nitrogen-phosphorus doping. Structural characterizations and the density function theory (DFT) calculations confirm that the interface effect of NiCoP/ Ni12P5 12 P 5 heterojunction can regulate the electronic structure of the catalyst to optimize the Gibbs free energy of hydrogen (Delta GH*); Delta G H* ); simultaneously, the defect-rich layered nanoarrays can expose more active sites, shorten mass transfer distance, and generate a self-supporting structure for in-situ reinforcing the structural stability. As a result, this NiCoP/Ni12P5@NF 12 P 5 @NF catalyst exhibits favorable electrocatalytic performance, which simply needs overpotentials of 100 mV for HER and 310 mV for OER, respectively, at a current density of 10 mA & sdot;cm-2. & sdot; cm- 2 . The anion exchange membrane electrolyzer assembled with this NiCoP/Ni12P5@NF 12 P 5 @NF as both anode and cathode catalysts can operate stably for 200 hat a current density of 100 mA & sdot;cm- & sdot; cm- 2 with an insignificant voltage decrease. This work may provide some inspiration for the further rational design of inexpensive non-noble multifunctional electrocatalysts and electrode materials for water splitting to generate hydrogen.