Monolayer carbon-encapsulated Mo-doped Ni nanoparticles anchored on single-wall carbon nanotube film for total water splitting

Electrochemical water splitting is regarded as a sustainable and cost-effective route for the production of hydrogen. However, the high-cost and poor stability of traditional rare-earth metal-based electrocatalysts make it difficult to yield hydrogen economically. Here, we report an efficient and durable film electrocatalyst of N-doped monolayer carbon encapsulated Mo-doped ultrafine Ni nanoparticles anchored on single-wall carbon nanotube network (NMoNi/SWCNT) for total water splitting in an alkaline solution. The single layer carbon prevents oxidation of encapsulated Ni and Mo species and facilitates desired electronic structure modulation to achieve a high catalytic activity. Hence, the freestanding NMoNi/SWCNT film catalyst shows low overpotentials of 255 mV and 130 mV to attain a current density of 10 mA cm−2 for oxygen evolution reaction and hydrogen evolution reaction, respectively, with a good stability. More importantly, the NMoNi/SWCNT film only requires a potential of 1.6 V to reach a current density of 20 mA cm−2 when employed as both anode and cathode for a total water splitting.