Modulation of Reactive Hydrogen Adsorbed on Dual-Active Site NiMoO<sub>4</sub> Nanocubes for Reduction of Nitrate to Ammonia
Dongrun Li, Jingru Chen, Shuchun Sun, Chuncheng Xu, Yuliang Sun, Hongyu Mou, Debao Wang, Caixia Song
Abstract
Development of highly active and selective electrocatalysts for the reduction of nitrate (NO 3 – ) to ammonia is critical for the production of green ammonia. Herein, we designed and synthesized NiMoO 4 nanocubes as an efficient electrocatalyst for nitrate reduction using deep eutectic solvents (DESs) as synthesis media. By constructing Mo and Ni dual-active sites, Mo facilitates NO 3 – adsorption/association, and Ni acts as an active hydrogen (*H) donating center. The amount and destination of *H can be regulated, which can effectively enhance the activity of the NO 3 – reduction to NH 3 reaction (NO 3 – RR). The optimized sample possessed excellent NO 3 – RR activity. An NH 3 –N selectivity of up to 96.94% and a Faraday efficiency of up to 96.13% can be achieved at −0.4 V in a neutral solution. The catalytic NO 3 – RR mechanism was also investigated by density functional theory (DFT) calculations. This dual-active site electrocatalyst provides an alternative idea for the synthesis and application of high-performance NO 3 – RR catalysts.