One-step construction of NiCo alloy particles encapsulated in N-doped carbon frameworks application for overall water splitting

The development of electrolyzed water catalyst with high activity, low cost, and long-term stability is still a challenge. This work reports a convenient strategy for synthesizing N-doped carbon-coated nickel-cobalt alloy particles (NiCo@NC) composites via a one-step high-temperature carbon reduction method. Among all the catalysts, Ni2Co1@NC shows the best OER and HER activities. In 1 M KOH system, the electrocatalyst Ni2Co1@NC requires only 346 mV to reach 50 mA cm−2 for OER and 189 mV to reach 10 mA cm−2 for HER. Tafel slope values are 50.1 and 83.9 mv dec−1 for OER and HER, respectively. In the 25 h HER and OER stability test for Ni2Co1 @NC catalyst, the current density hardly decays, and even slightly increases. In addition, the Ni2Co1@NC used as the dual functional catalyst achieves the voltage of 1.9 V at 50 mA cm−2. The enhanced catalytic performance is closely related to the microstructure and composition of nitrogen-doped carbon coated NiCo alloy catalysts. This approach provides a facile strategy for designing highly active and low-cost bifunctional catalysts.