Optimizing band structure of CoP nanoparticles via rich‐defect carbon shell toward bifunctional electrocatalysts for overall water splitting

Transition-metal phosphides (TMPs) with high catalytic activity are widely used in the design of electrodes for water splitting. However, a major challenge is how to achieve trade-off between and stability TMPs. Herein, novel method synthesizing CoP nanoparticles encapsulated rich-defect carbon shell (CoP/DCS) developed through self-assembly modified polycyclic aromatic molecules. The graft removal high-activity C–N bonds molecules render controllable crystallite defects shell. density functional theory calculation indicates that unpaired electrons could effectively tailor band structure CoP. Benefiting from improved corrosion resistance, CoP/DCS delivers outstanding difunctional hydrogen evolution reaction (88 mV) oxygen (251 performances at 10 mA cm−2 current density. Furthermore, coupled electrolyzer as both cathode anode presents ultralow cell voltages 1.49 V long-time stability. This strategy improve TMPs electrocatalyst rich-DCS heterogeneous will inspire other transition metal compound electrocatalysts