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Direct seawater electrolysis presents a promising route for grid‐scale green hydrogen (H2) production without reliance on scarce freshwater. However, it is severely hampered by high energy consumption (> 4.3–5.73 kWh m−3 H2) and harmful chlorine corrosion. Herein, an energy‐saving and chlorine‐free H2 production system by coupling seawater splitting and upcycling of polyethylene terephthalate (PET) waste into value‐added glycolic acid (GA) over a Pd─CuCo2O4 catalyst is reported. An ultra‐low potential of 1.15 V versus RHE is required to achieve an industry‐level current density of 600 mA cm−2, which reduces electricity cost to 2.45 kWh m−3 H2. Notably, this system maintains 1.6 A for longer than 100 h, demonstrating excellent stability. Experimental and theoretical results unveil that 1) the specific adsorption of PET‐derived ethylene glycol (EG) on Pd enhances the catalytic performance, and the downshifted d‐band center of Pd accelerates the desorption of GA to prevent over‐oxidation; 2) the strong adsorption of OH− on CuCo2O4 synergistically promotes EG electrooxidation (EGOR) and forms a negative charge layer that effectively repels Cl− by electrostatic repulsion, thus preventing chlorine corrosion. This work may provide new opportunities for H2 production and value‐added GA from vast marine resources and PET waste. [ABSTRACT FROM AUTHOR]

Adipic acid (AA) is a crucial feedstock for nylon polymers, and is industrially produced by thermal oxidation of cyclohexanone/cyclohexanol mixture (KA oil). However, this process consumes large quantities of corrosive nitric acid as oxidants, while emits ozone‐depleting greenhouse gas N2O. Here, an electrocatalytic strategy for selective oxidation of KA oil to AA coupled with H2 evolution over a Co3O4/graphdiyne cooperative catalyst (Co3O4/GDY) is reported. The Co3O4/GDY displays high electrooxidation activity of KA oil to AA (100 mA cm−2 at ≈1.5 V vs RHE), outperforming all the reported findings. Detailed ex situ and in situ experimental studies, theoretical calculations, and molecular dynamic simulations reveal that GDY not only facilitates the enrichment of cyclohexanone on the catalyst surface in aqueous medium, but also upshifts the d‐band center of Co sites, strengthening the adsorption/activation of cyclohexanone. This study offers a green route for AA synthesis and proposes a GDY interface engineering strategy for efficient electrooxidation. [ABSTRACT FROM AUTHOR]

Efficient and durable electrocatalysts are instrumental in enabling next‐generation fuel cell technologies. At present, expensive precious metals are used as state‐of‐the‐art catalysts. In this report, cost‐effective nanosized tantalum‐based alternatives are synthesized for the first time via a green and scalable laser pyrolysis method as bifunctional catalysts for direct peroxide–peroxide fuel cells. This rapid laser pyrolysis strategy allows for the production of nanoparticles at a laboratory scale of grams per hour, compatible with a detailed exploration of the functional properties of as‐synthesized nanoparticles. By varying the precursor ratio between ammonia and tantalum ethanolate, five tantalum‐based nanomaterials (TaNOC) are prepared with crystalline phases of Ta2O5, Ta4N5, Ta3N5, and TaN in tunable ratios. Electrochemical studies in neutral and alkaline conditions demonstrate that Ta4N5 is the active component for both H2O2 oxidation and reduction. Kinetic isotope effect studies show that protons are involved at or before the rate‐determining step. Long‐term stability studies indicate that Ta3N5 grants surfactant‐free TaNOC‐enhanced longevity during electrocatalytic operations. Taken together, bifunctional TaNOC can act as active and robust electrocatalysts for H2O2 reduction and oxidation. Laser pyrolysis is envisioned to produce refractory metal nanomaterials with boosted corrosion resistance for energy catalysis. [ABSTRACT FROM AUTHOR]

Electro‐reforming of Polyethylene‐terephthalate‐derived (PET‐derived) ethylene glycol (EG) into fine chemicals and H2 is an ideal solution to address severe plastic pollution. Here, we report the electrooxidation of EG to glycolic acid (GA) with a high Faraday efficiency and selectivity (>85 %) even at an industry‐level current density (600 mA cm−2 at 1.15 V vs. RHE) over a Pd−Ni(OH)2 catalyst. Notably, stable electrolysis over 200 h can be achieved, outperforming all available Pd‐based catalysts. Combined experimental and theoretical results reveal that 1) the OH* generation promoted by Ni(OH)2 plays a critical role in facilitating EG‐to‐GA oxidation and removing poisonous carbonyl species, thereby achieving high activity and stability; 2) Pd with a downshifted d‐band center and the oxophilic Ni can synergistically facilitate the rapid desorption and transfer of GA from the active Pd sites to the inactive Ni sites, avoiding over‐oxidation and thus achieving high selectivity. [ABSTRACT FROM AUTHOR]

The recycling of plastic waste is one of the most urgent issues in the 21st century owing to its detrimental impact on the environment and human health. However, it is greatly challenging to develop more efficient, low-cost and general methods capable of selectively converting plastic waste into added-value and separable chemicals while restricting their distribution. Here, we report a general electrocatalytic strategy for the selective upcycling of various polyester plastics into added-value chemicals by a CuCo2O4/Ni foam catalyst under mild conditions. In particular, polyethylene terephthalate (PET) was upcycled into terephthalate and formate with high efficiency and selectivity (>86%) even at a high current density of 100 mA cm−2. The electrocatalytic reaction mechanism was thoroughly elucidated by electrochemical in situ FTIR, NMR and DFT calculations. This work not only develops a superior electrocatalyst for upcycling various polyester plastics, but also provides guidance for the design of new and efficient electrocatalysts. [ABSTRACT FROM AUTHOR]

To control proton delivery across biological membranes, we synthesized a photoresponsive molecular switch and incorporated it in a lipid layer. This proton gate was reversibly activated with 390 nm light (Z-isomer) and then deactivated by 360 nm irradiation (E-isomer). In a lipid layer this stimuli responsive proton gate allowed the regulation of proton flux with irradiation to a lipid-buried O2 reduction electrocatalyst. Thus, the catalyst was turned on and off with the E-to-Z interconversion. This light-induced membrane proton delivery system may be useful in developing any functional device that performs proton-coupled electron-transfer reactions. [ABSTRACT FROM AUTHOR]