This review underlines the strategies to suppress HER for selective NRR in view of proton-/electron-transfer kinetics, thermodynamics, and electrocatalyst design on the basis of deep understanding for NRR mechanisms.

This review underlines innovative design strategies for CO2RR system, also distinctively presents the current status and new trend.

Integrated/cascade plasma-enabled N2 oxidation and electrocatalytic NO x – (where x = 2, 3) reduction reaction (pNOR-eNO x –RR) holds great promise for the renewable synthesis of ammonia (NH3). However, the corresponding activated effects and process of plasma toward N2 and O2 molecules and the mechanism of eNO x –RR to NH3 are unclear and need to be further uncovered, which largely limits the large-scale deployment of this process integration technology. Herein, we systematically investigate the plasma-enabled activation and recombination processes of N2 and O2 molecules, and more meaningfully, the mechanism of eNO x –RR at a microscopic level is also decoupled using copper (Cu) nanoparticles as a representative electrocatalyst. The concentration of produced NO x in the pNOR system is confirmed as a function of the length for spark discharge as well as the volumetric ratio for N2 and O2 feeding gas. The successive protonation process of NO x – and the key N-containing intermediates (e.g., −NH2) of eNO x –RR are detected with in situ infrared spectroscopy. Besides, in situ Raman spectroscopy further reveals the dynamic reconstruction process of Cu nanoparticles during the eNO x –RR process. The Cu nanoparticle-driven pNOR-eNO x –RR system can finally achieve a high NH3 yield rate of ∼40 nmol s–1 cm–2 and Faradaic efficiency of nearly 90%, overperforming the benchmarks reported in the literature. It is anticipated that this work will stimulate the practical development of the pNOR-eNO x –RR system for the green electrosynthesis of NH3 directly from air and water under ambient conditions.