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Zn‐based catalytic batteries, recognized as eco‐friendly alternatives, are attracting significant research interest for their applications in energy storage, conversion, pollutant degradation, and ammonia synthesis. This review compiles the latest developments in Zn‐nitrogen oxides (NOx) batteries, covering various types including Zn‐nitrate, Zn‐nitric oxide, and Zn‐nitrite batteries. This study explores the electrode reactions and structural evolutions of these batteries, emphasizing the different challenges posed by cathodic reactions. Advanced design strategies for cathode materials, such as inhibiting hydrogen production, utilizing tandem sites, and enhancing reactant enrichment, are presented and evaluated. These strategies have markedly improved NOx reduction performance and have driven significant progress in Zn‐NOx battery. The future directions for research are outlined, highlighting the need for more efficient NOx reduction catalysts, optimization of Zn anodes, development of alternative metal anodes, battery structure improvements, and exploration of charging reactions. Addressing these challenges is crucial for advancing the development of eco‐friendly and high‐energy‐density Zn‐NOx batteries. [ABSTRACT FROM AUTHOR]

Ammonia is emerging as a liquefied and renewable‐energy carrier of global interest in the future. The electrochemical reduction of nitrate is widely acknowledged as an alternative to the traditional Haber–Bosch process for ammonia production. However, it is observed that certain catalysts can undergo spontaneous oxidation–reduction reactions with nitrate to some extent, leading to the calculated ammonia Faradaic efficiency exceeding 100%. However, there is a lack of accurate experimental validation as well as effective solutions. To address these problems, it is verified that the spontaneous reaction between the catalyst and nitrate impacts on the calculation of electrocatalytic nitrate reduction performance. Meanwhile, an updated and optimized experimental strategy is proposed to address the interference caused by the spontaneous reaction. This work will significantly contribute to more accurate and reliable electrocatalytic nitrate reduction research. [ABSTRACT FROM AUTHOR]

The resource recovery of heavy metals from effluent has significant environmental implications and potential commercial value. Chromium phosphide nanoparticles embedded in a nitrogen‐/phosphorus‐doped porous carbon matrix (CrP/NPC) are synthesized via a consecutive Cr6+ leachate treatment and resource recovery process. Electrochemical testing shows that CrP/NPC shows excellent nitrogen reduction reaction (NRR) performance, which yields the highest NH3 production rate of 22.56 μg h−1 mg−1cat. and Faradaic efficiency (16.37%) at −0.5 V versus the reversible hydrogen electrode in a 0.05 M Na2SO4 aqueous solution, as well as robust catalytic stability. The isotopic experiments using 15N2 as a nitrogen source confirm that the detected NH3 is derived from the NRR process. Finally, density functional theory (DFT) calculations show that the electron deficiency environment of the Cr site can significantly reduce the barrier of the NRR process and promote the formation of intermediate species. [ABSTRACT FROM AUTHOR]

Alkaline membrane water electrolysis is a promising production technology, and advanced electrocatalyst and membrane electrode design have always been the core technology. Herein, an ion-exchange method and an environmentally friendly in situ green phosphating strategy are successively employed to fabricate Ru-Ru 2 P heterogeneous nanoparticles by using hydroxyapatite (HAP) as a phosphorus source, which is an exceptionally active electrocatalyst for hydrogen evolution reaction (HER). Density functional theory calculation results reveal that strong electronic redistribution occurs at the heterointerface of Ru-Ru 2 P, which modulates the electronic structure to achieve an optimized hydrogen adsorption strength. The obtained Ru-Ru 2 P possesses excellent HER performance (24 mV at 10 mA cm -2 ) and robust stability (1000 mA cm -2 for 120 h) in alkaline media. Furthermore, an environmentally friendly membrane electrode with a sandwich structure is assembled by HAP nanowires as an alkaline membrane, Ru-Ru 2 P as a cathodic catalyst, and NiFe-LDH as an anodic catalyst, respectively. The voltage of (-) Ru-Ru 2 P || NiFe-LDH/CNTs (+) (1.53 V at 10 mA cm -2 ) is lower than that of (-) 20 wt% Pt/C || RuO 2 (+) (1.60 V at 10 mA cm -2 ) for overall water splitting. Overall, the studies not only design an efficient catalyst but also provide a new route to achieve a high-stability electrolyzer for industrial H 2 production., (© 2023 Wiley-VCH GmbH.)