Gel-Derived Amorphous Bismuth-Nickel Alloy Promotes Electrocatalytic Nitrogen Fixation via Optimizing Nitrogen Adsorption and Activation

To achieve the electrochemical nitrogen reduction reaction (NRR) for efficient and sustainable NH3 production, catalysts should exhibit high selectivity and activity with optimal adsorption energy. Herein we developed a three-dimensional (3D) amorphous BiNi alloy toward a significantly enhanced NRR compared with its crystalline and metal counterparts. Ni alloying enables the chemisorption of nitrogen and the lower free-energy change for the *NNH formation, and the 3D alloy electrocatalyst exhibits high catalytic activity for NH3 production with a yield rate of 17.5 mu g h(-1) mg(cat)(-1) and Faradaic efficiency of 13.8 %. The enhanced electron transfer and increased electrochemical surface area were revealed in the interconnected porous scaffold, affording it sufficiently efficient and stable activity for potential practical applications. This work offers new insights into optimizing the adsorption energy of reactants and intermediates combined with tuning the crystallinity of NRR electrocatalysts.

Automated summary

This study developed a 3D amorphous BiNi alloy that significantly enhances the NRR efficiency compared to crystalline and metal counterparts. Ni alloying improves the chemisorption of nitrogen, resulting in higher NH3 production rate and Faradaic efficiency. The interconnected porous scaffold in the 3D alloy enables enhanced electron transfer and increased electrochemical surface area, making it efficient and stable for potential practical applications.