Large-scale and One-step Synthesis of CoP/NC as a Highly Active Electrocatalyst for the Hydrogen Evolution Reaction and Oxygen Reduction Reaction

For clean and renewable energy research, developing non-noble metal electrocatalysts with high activity and stability for the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) is critical. Herein, cobalt phosphide/N-doped carbon (CoP/NC) was synthesized by an extremely convenient approach. Compared with pure CoP, NC wrapped around CoP nanoparticles, which prevented the agglomeration and improved electron transfer of CoP. The obtained CoP/NC exhibited better activity than pure CoP, which has a low overpotential (η 10 =139/248 mV) and a small Tafel slope (59/82 mV dec −1 ) in 0.5 M H 2 SO 4 and 1 M KOH for the HER. CoP/NC exhibited excellent stability with no obvious change in activity for the HER after 5000 cycles. CoP/NC also had high ORR activity, which gave a more positive half-potential (0.85 V) and onset potential (0.9 V) than pure CoP at 1600 rpm in 0.1 M KOH.