Nanoporous NiBi catalyst for efficient electrochemical N2 fixation

Abstract

Electrochemical nitrogen reduction reaction (NRR) in ambient condition provides a sustainable avenue for large-scale NH3 production. However, the development of effective and durable NRR catalysts to promote NH3 synthesis rate and Faraday efficiency (FE) remains a challenge due to the inertness of the N≡N bond. Herein, porous NiBi catalysts which provides abunant active sites were prepared by chemical dealloying of the precursor. Combining theoretical calculations and experimental verification, it is demonstrated that the synergistic effect of Ni and NiBi facilitates the adsorption of N2, inhibits the competition reaction, and reduces the free energy of intermediates (*NNH). Porous Ni91.5Bi8.5 exhibits high catalytic activity for NH3 formation with a yield of 18.35 μg h−1 mg−1 and a FE of 51.12% at −0.3 V vs. RHE, outperforming most reported NRR electrocatalysts under ambient conditions. This strategy is an effective and universal technique for synthesizing catalysts that shows great potential in energy conversion applications.