Dual-Intermetallic Heterostructure on Hierarchical Nanoporous Metal for Highly Efficient Nitrate Reduction Electrocatalysis.

Electrocatalytic reduction of nitrate to ammonia is a promising strategy for green ammonia production. However, the nitrate reduction reaction (NORR) still suffers from the sluggish kinetics of hydrogenation process and subsequent ammonia desorption. Herein, the nanoporous Cu/CuSn heterostructure is prepared by dealloying and serves as an efficient catalyst for NORR. The Cu/CuSn heterostructure improves the affinity of alkali-ionized water, promoting intermediate hydrogenation via enhanced active hydrogen supply. Moreover, NH desorption can also be accelerated by the introduction of the CuSn phase. As a result, the np-Cu/CuSn catalyst exhibits a high ammonia yield of 1.2 mmol h cm with an excellent Faradaic efficiency of 97%. This work provides an intriguing strategy to enhance the catalytic activity by regulating the intermediates adsorption.