Promotion for Full Water Splitting toward Vanadium-Incorporated MoO2–MoNi4 Hybrid Nanoarrays

To explore highly active non-noble electrocatalysts toward full water splitting, the incorporation of other metal elements to the host electrocatalyst is required, especially for previously reported highly efficient MoO2–MoNi4 (MoNi in short). Herein, to lessen the energy cost in full water splitting, the vanadium-incorporated MoO2–MoNi4 (VMoNi in short) hybrid nanoarray self-supported on nickel foam is prepared through a simple way. Compared with the Mo–Ni binary electrocatalyst, vanadium incorporation can obviously boost oxygen evolution reaction (OER) activity while almost keeping the perfect hydrogen evolution reaction (HER) ability, for it merely requires 202 and 17 mV for 10 mA cm–2 working current density toward OER and HER, respectively. Furthermore, it displays outstanding performance toward full water splitting, merely requiring 1.45 V for 10 mA cm–2 and 1.61 V for 100 mA cm–2 in water electrolysis with keeping the voltage stable in tens of hours at 250 mA cm–2. This work highlights the significance in large-scale hydrogen production from water electrolysis with the help of exploring non-noble materials, an important milestone in converting the renewable energy to hydrogen energy.