Metal–Organic Framework-Derived CoWP@C Composite Nanowire Electrocatalyst for Efficient Water Splitting

Practical application of electrochemical water splitting demands durable, efficient, and non-noble metal catalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, we report a new hydrogen evolution nanowire electrocatalyst, consisting of S-doped CoWP nanoparticles embedded in S- and N-doped carbon matrix (S-CoWP@(S,N)-C), which is in situ transformed from Hofmann-type (Co, W)-based metal–organic framework (MOF) nanowires. Because of S and N doping to the carbon matrix and the S doping to CoWP nanoparticles, the obtained S-CoWP@(S,N)-C catalyst reaches a current density of −10 mA cm–2 at −35 and −67 mV (vs RHE) in acidic and alkaline electrolytes, respectively. Powered by a lead halide perovskite solar cell, an unassisted two-electrode solar water-splitting device using MOF-derived S-CoWP@(S,N)-C HER electrocatalysts and S-CoW@(S,N)-C OER electrocatalysts displays a solar-to-hydrogen conversion efficiency of 10.98%. Our method is highly applicable for developing robust electrocatalysts toward efficient and low-cost solar-driven water splitting.