Efficient electrocatalytic conversion of N2 to NH3 on NiWO4 under ambient conditions

The development of highly efficient and inexpensive catalysts is still a tremendous challenge for the electrocatalytic nitrogen reduction reaction (NRR), which is a promising alternative to high-temperature and high-pressure industrial technologies for the synthesis of NH3. Herein, we report a facile and large scale strategy exploiting a porous non-precious bimetallic oxide of NiWO4 for the NRR under ambient conditions. Benefiting from the above-mentioned merits, the designed electrocatalyst achieved outstanding catalytic activities in both 0.1 M HCl (NH3 yield: (40.05 ± 1.45) μg h-1 mg-1cat., Faraday efficiency (FE): (19.32 ± 0.68)% at -0.3 V) and 0.1 Na2SO4 (NH3 yield: (23.14 ± 1.75) μg h-1 mg-1cat., Farady efficiency: (10.18 ± 0.62)% at -0.3 V), and these efficiencies are superior to most of the reported non-precious metals for the NRR. Furthermore, the prepared catalyst presented excellent stability in both acidic and neutral media for up to 20 h. This work opens a constructive avenue for optimizing the catalytic performance of metal oxides and other transition metal-based catalysts for NRRs.