 This review focuses on introducing different modifications and regulatory mechanisms to improve the electrochemical performance of NO slash NO3 reduction ENR for nitrification. These include crystal facet engineering, heteroatom doping, hetero structures, surface vacancy engineering, and single atom structures. The goal is to increase the reactivity, selectivity, faraday efficiency, and stability of ENR catalysts. This article was authored by Guilin Liu, Sanshuang Gao, Qian Liu, and others.