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Co‐based material catalysts have shown attractive application prospects in the 2 e− oxygen reduction reaction (ORR). However, for the industrial synthesis of H2O2, there is still lack of Co‐based catalysts with high production yield rate. Here, novel cyclodextrin‐supported Co(OH)2 cluster catalysts were prepared via a mild and facile method. The catalyst exhibited remarkable H2O2 selectivity (94.2 % ~ 98.2 %), good stability (99 % activity retention after 35 h), and ultra‐high H2O2 production yield rate (5.58 mol gcatalyst−1 h−1 in the H‐type electrolytic cell), demonstrating its promising industrial application potential. Density functional theory (DFT) reveals that the cyclodextrin‐mediated Co(OH)2 electronic structure optimizes the adsorption of OOH* intermediates and significantly enhances the activation energy barrier for dissociation, leading to the high reactivity and selectivity for the 2 e− ORR. This work offers a valuable and practical strategy to design Co‐based electrocatalysts for H2O2 production. [ABSTRACT FROM AUTHOR]

Developing efficient electrocatalysts for CO2 reduction to syngas with tunable H2/CO ratios and high total faradaic efficiency is challenging. Herein, we report an effective catalyst composed of in situ reconstructed AgZn3 nanoparticles and Zn nanoplates for syngas synthesis, showing nearly 100% Faraday efficiency to syngas with a tunable H2/CO ratio from 2 : 1 to 1 : 2. Moreover, the in situ electrochemical measurements coupled with theoretical calculations disclose that the Zn site in AgZn3 nanoparticles and the hollow site between Ag and Zn in AgZn3 are the possible active sites for CO and H2 generation, respectively. This work has guiding significance for designing dual site catalysts for CO2 electroreduction to tunable syngas. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrate (NO3−) reduction reaction (NITRR) is an inspiring route for ammonia (NH3) synthesis at ambient condition. The metallic Cu‐based material with low cost and high activity is one of the most promising electrocatalysts for NITRR. However, due to the weaker atomic H*‐providing capacity, the produced intermediate—nitrite tends to accumulate on its surface, leading to unsatisfactory NH3 selectivity and Faradic efficiency (FE). Herein, a novel and facile O2/Ar plasma oxidation and subsequent electro‐reduction strategy is developed to synthesize a kind of metastable phase Cu. Excitingly, the metastable phase Cu demonstrates superior NITRR performance to conventional phase Cu with high NH4+ selectivity (97.8%) and FE (99.8%). Density function theory (DFT) calculations reveal that the upshift of the d‐band center to near the Fermi level in metastable phase Cu contributes to the enhanced activity, while the relatively strong adsorption of H* facilitates the conversion from NO2*/NO* to NOOH*/NOH* and thus ensures high selectivity and FE. Furthermore, when evaluated as cathode material in Zn‐NO3− battery, high power density (7.56 mW cm−2) and NH4+ yield (76 µmol h−1 cm−2) are achieved by the metastable phase Cu‐based battery. [ABSTRACT FROM AUTHOR]

Electrochemical synthesis of hydrogen peroxide (H2O2) through 2e– oxygen reduction reaction is an effective approach to replace anthraquinone process. However, most reported electrocatalysts work effectively in alkaline medium in which H2O2 will easily decompose into water. It is still of great challenge to develop cost‐effective electrocatalysts with high activity and selectivity for electrocatalytic H2O2 production in acidic media. Herein, it is first theoretically demonstrated that the adsorption energy of OOH* intermediate on carbon can be optimized by embedding Co nanoparticles (Co NPs) and tuning oxygen‐containing functional groups, ensuring high activity and selectivity. Guided by density functional theory calculations, highly porous open carbon nanocages with embedded Co NPs are designed and synthesized by template‐engaged method. The pyrolysis temperature can effectively modulate the electronic and pore structure of carbon nanocages. Impressively, the optimized carbon nanocages synthesized at 700 °C (P‐Co@C‐700) with highest percentage of –C–O–C group and defects, largest specific surface area (1351 m2 g–1), and mesoporous structure exhibit high selectivity up to 94% toward H2O2 production in 0.1 m HClO4. Furthermore, the P‐Co@C‐700 nanocages display promising application for efficient electro‐Fenton degradation of model organic pollutant. [ABSTRACT FROM AUTHOR]