Homologous Catalysts Based on Fe-Doped CoP Nanoarray toward High-Performance Full Water Splitting under Benign Conditions

The design and development of earth-abundant electrocatalysts for efficient full water splitting under mild conditions are highly desired but still remain a challenging task. In this study, we describe the development of homologous Fe-doped Co-based nanoarray as complementary catalysts for high-performance and durable water splitting in near-neutral media. Fe-doped Co-phosphate-borate nanoarray on carbon cloth (Fe-Co-Pi-Bi/CC) derived from Fe-doped CoP nanoarray on CC (Fe-CoP/CC) via oxidative polarization behaves as a highly active bimetallic electrocatalyst for water oxidation with the demand of overpotential of 382 mV to afford a geometrical catalytic current density of 10 mA cm-2 in 0.1 M potassium borate (K-Bi, pH: 9.2). Fe-CoP/CC is also superior in activity for hydrogen evolution reaction, capable of driving 10 mA cm-2 at overpotential of only 175 mV in 0.1 M K-Bi. The two-electrode water electrolyser using Fe-Co-Pi-Bi/CC as anode and Fe-CoP/CC as cathode achieves 10 mA cm-2 water splitting current at a cell voltage of 1.95 V with strong long-term electrochemical durability.