We report the synthesis of two-dimensional metalorganic frameworks (MOFs) on nickel foam (NF) by assembling nickel chloride hexahydrate and 1,1'-ferrocenedicarboxylic acid (NiFc-MOF/NF). The NiFc-MOF/NF exhibits superior oxygen evolution reaction (OER) performance with an overpotential of 195 mV and 241 mV at 10 and 100 mA cm À2 , respectively under alkaline conditions. Electrochemical results demonstrate that the superb OER performance originates from the ferrocene units that serve as efficient electron transfer intermediates. Density functional theory calculations reveal that the ferrocene units within the MOF crystalline structure enhance the overall electron transfer capacity, thereby leading to a theoretical overpotential of 0.52 eV, which is lower than that (0.81 eV) of the state-of-the-art NiFe double hydroxides.

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.

The recycling of plastic wastes is one of the urgent issues in the 21st century owing to its detrimental impact on the environment and human health. However, it has great...

Transition-metal carbides (TMCs) are important materials for a variety of applications and industrial processes, in part because of their variable crystal structures and surfaces. However, the synthesis of TMCs often proceeds through metastable phases during particle growth, the appearance of which cannot be described by traditional phase diagrams. Here, we use density functional theory calculations and thermodynamic analyses to construct particle size-dependent phase diagrams for Mo and W carbides and reveal the relationships between phase stability and TMC nanoparticle size. We compute size-dependent phase diagrams for a wide range of Mo carbide and W carbide phases, determine predicted crystallization pathways during synthesis, and compare model results with experimental data. We provide insights for the influence of nanoparticle size on TMC nucleation and growth during synthesis and provide a computationally guided road map for navigating the synthesis of target TMC surfaces and phases.

We report the synthesis of two-dimensional metalorganic frameworks (MOFs) on nickel foam (NF) by assembling nickel chloride hexahydrate and 1,1'-ferrocenedicarboxylic acid (NiFc-MOF/NF). The NiFc-MOF/NF exhibits superior oxygen evolution reaction (OER) performance with an overpotential of 195 mV and 241 mV at 10 and 100 mA cm À2 , respectively under alkaline conditions. Electrochemical results demonstrate that the superb OER performance originates from the ferrocene units that serve as efficient electron transfer intermediates. Density functional theory calculations reveal that the ferrocene units within the MOF crystalline structure enhance the overall electron transfer capacity, thereby leading to a theoretical overpotential of 0.52 eV, which is lower than that (0.81 eV) of the state-of-the-art NiFe double hydroxides.

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.

Net-zero carbon strategies and green synthesis methodologies are key to realizing the United Nations’ sustainable development goals (SDGs) on a global scale. An electrocatalytic glycerol oxidation reaction (GOR) holds the promise of upcycling excess glycerol from biodiesel production directly into precious hydrocarbon commodities that are worth orders of magnitude more than the glycerol feedstock. Despite years of research on the GOR, the synthesis process of nanoscale electrocatalysts still involves (1) prohibitive heat input, (2) expensive vacuum chambers, and (3) emission of toxic liquid pollutants. In this paper, these knowledge gaps are closed via developing a laser-assisted nanomaterial preparation (LANP) process to fabricate bimetallic nanocatalysts (1) at room temperature, (2) under an ambient atmosphere, and (3) without liquid waste emission. Specifically, PdCu nanoparticles with adjustable Pd:Cu content supported on few-layer graphene can be prepared using this one-step LANP method with performance that can rival state-of-the-art GOR catalysts. Beyond exhibiting high GOR activity, the LANP-fabricated PdCu/C nanomaterials with an optimized Pd:Cu ratio further deliver an exclusive product selectivity of up to 99% for partially oxidized C3 products with value over 280000-folds that of glycerol. Through DFT calculations and in situ XAS experiments, the synergy between Pd and Cu is found to be responsible for the stability under GOR conditions and preference for C3 products of LANP PdCu. This dry LANP method is envisioned to afford sustainable production of multimetallic nanoparticles in a continuous fashion as efficient electrocatalysts for other redox reactions with intricate proton-coupled electron transfer steps that are central to the widespread deployment of renewable energy schemes and carbon-neutral technologies.

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