Study on the Plasma‐Induced Synthesis of P‐Ru‐Co(OH) 2 @PCC for the Electrochemical Reduction of Nitrate

The synthesis of value-added ammonia (NH₃) from nitrate-containing wastewater is crucial for green chemical manufacturing and wastewater treatment. However, achieving efficient electrocatalytic nitrate reduction reaction (NO₃RR) under neutral conditions remains challenging because of an imbalance between the supply and demand of active hydrogen, insufficient active sites, and sluggish reaction kinetics. To address this challenge, plasma-assisted micro-modulation of ruthenium (Ru)-doped cobalt hydroxide (Co(OH)₂) nanosheets induces surface restructuring under mild conditions. This process tunes the valence states of the constituent elements and creates abundant oxygen vacancies, thereby enhancing NO₃RR performance under neutral conditions. The results demonstrate that the P-Ru-Co(OH)₂@PCC catalyst, which was obtained following short-term treatment with H₂/Ar plasma, exhibits significantly enhanced NO₃RR activity. Specifically, the yield of ammonia reached 2.63 mg h^{- 1} cm^{- 2}. Theoretical calculations further confirmed that plasma regulation improved the catalyst's adsorption of NO₃ ^-, lowered the reaction energy barrier, and ultimately enhanced the overall activity of the catalyst in the NO₃RR process for ammonia synthesis.