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Abstract Electrosynthesis of alkyl carboxylic acids upon activating stronger alkyl chlorides at low‐energy cost is desired in producing carbon‐rich feedstock. Carbon dioxide (CO₂), a greenhouse gas, has been recognized as an ideal primary carbon source for those syntheses, and such events also mitigate the atmospheric CO₂level, which is already alarming. On the other hand, the promising upcycling of polyvinyl chloride to polyacrylate is a high energy‐demanding carbon‐chloride (C−Cl) bond activation process. Molecular catalysts that can efficiently perform such transformation under ambient reaction conditions are rarely known. Herein, we reveal a nickel (Ni)‐pincer complex that catalyzes the electrochemical upgrading of polyvinyl chloride to polyacrylate in 95 % yield. The activities of such a Ni electrocatalyst bearing a redox‐active ligand were also tested to convert diverse examples of unactivated alkyl chlorides to their corresponding carboxylic acid derivatives. Furthermore, electronic structure calculations revealed that CO₂binding occurs in a resting state to yield an η²‐CO₂adduct and that the C−Cl bond activation step is the rate‐determining transition state, which has an activation energy of 19.3 kcal/mol. A combination of electroanalytical methods, control experiments, and computational studies were also carried out to propose the mechanism of the electrochemical C−Cl activation process with the subsequent carboxylation step. 

Abstract Reductive hydrodechlorination is an effective approach to enhance the degradation rate of chlorinated herbicides such as alachlor, which are frequently detected in ground and surface water. In this study, a cobalt porphyrin complex with eight triazole units and alkyl chains,CoPor8T, was synthesized to catalyze the reductive hydrodechlorination of alachlor. Mechanistic study was performed using a combination of voltametric, spectroscopic, and electrospectroscopic techniques. A conversion yield of 84 % at −1.8 V vs. Fc/Fc⁺and chloride ion concentration of 96 % was obtained after electrocatalysis. This work provides a new avenue of using molecular catalysts for electrocatalytic chlorinated herbicide remediation. 

Abstract Redox flow batteries (RFB) have emerged as one of the most promising technologies for large‐scale energy storage owing to their high safety, long operation life, and decoupled design of energy and power. However, the problems of high cost and low energy density restrict their further development. The cost merit and tunable structure of organic redox‐active materials have prompted the development of organic RFBs. The solubility of the redoxmer is recognized as a parameter that contributes directly to the energy density. Herein, we focus on strategies for enhancing the solubility of organic redoxmers in aqueous RFBs. The effects of incorporating different hydrophilic functional groups on the solubility of the redoxmer and its effect on the performance of other batteries are systematically and exhaustively described. Other strategies, such as molecular symmetry tuning and employing more soluble counterions and cosolvents, are also summarized. The development trends and prospects for organic RFBs are also discussed. 

Abstract Electrocatalytic hydrogen gas production is considered a potential pathway towards carbon‐neutral energy sources. However, the development of this technology is hindered by the lack of efficient, cost‐effective, and environmentally benign catalysts. In this study, a main‐group‐element‐based electrocatalyst,SbSalen, is reported to catalyze the hydrogen evolution reaction (HER) in an aqueous medium. The heterogenized molecular system achieved a Faradaic efficiency of 100 % at −1.4 V vs. NHE with a maximum current density of −30.7 mA/cm². X‐ray photoelectron spectroscopy of the catalyst‐bound working electrode before and after electrolysis confirmed the molecular stability during catalysis. The turnover frequency was calculated as 43.4 s⁻¹using redox‐peak integration. The kinetic and mechanistic aspects of the electrocatalytic reaction were further examined by computational methods. This study provides mechanistic insights into main‐group‐element electrocatalysts for heterogeneous small‐molecule conversion.