Construction of Fe-doped CoP with hybrid nanostructures as a bifunctional catalyst for overall water splitting

With the open skeleton structures, adjustable active sites and homogeneous catalytic centers, PBA-based materials had promising applications in electrochemical water splitting. Herein, we reported a PBA derived Fe0.25-CoP electrocatalyst with hybrid nanostructures, which offered a large specific surface area and active sites for HER and OER, respectively. The as-synthesized Fe0.25-CoP catalyst possessed remarkable catalytic performance and durability, which exhibited overpotentials of 262 mV for OER and 111 mV for HER at 10 mA cm-2, and requiring a voltage of merely 1.57 V to achieve a current density of 10 mA cm-2 for electrocatalytic water splitting process. The preeminent activity of Fe0.25-CoP was mainly ascribed to the framework structures of Co-PBA and appropriate doping of Fe3+ which regulated the electronic structures and morphology of Fe0.25-CoP. In addition, the partial phosphating strategy retained active centers for OER in Co-PBA, which further enhanced through the catalysis of Fe3+. In short, rational design and regulation of catalyst structures and composition was a promising approach for the development of highly efficient water splitting catalysts.