Identification of Active Sites Formed on Cobalt Oxyhydroxide in Glucose Electrooxidation

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(15)

Опубликована: Фев. 18, 2023

Transition-metal-based oxyhydroxides are efficient catalysts in biomass electrooxidation towards fossil-fuel-free production of valuable chemicals. However, identification active sites remains elusive. Herein, using cobalt oxyhydroxide (CoOOH) as the archetype and electrocatalyzed glucose oxidation reaction (GOR) model reaction, we track dynamic transformation electronic atomic structure catalyst a suite operando ex situ techniques. We reveal that two types reducible Co3+ -oxo species afforded for GOR, including adsorbed hydroxyl on ion (μ1 -OH-Co3+ ) di-Co3+ -bridged lattice oxygen (μ2 -O-Co3+ ). Moreover, theoretical calculations unveil μ1 is responsible oxygenation, while μ2 mainly contributes to dehydrogenation, both key oxidative steps glucose-to-formate transformation. This work provides framework mechanistic understanding complex near-surface chemistry metal electrorefining.

Язык: Английский

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Polyhedral Coordination Determined Co‐O Activity for Electrochemical Oxidation of Biomass Alcohols

Advanced Energy Materials, Год журнала: 2023, Номер 13(37)

Опубликована: Авг. 11, 2023

Abstract Earth‐abundant transition metal oxides are promising electrocatalysts for oxidation of biomass alcohols. Here, CoO and Co 3 O 4 selected as representative cobalt oxide catalysts grown on carbon fiber paper (CFP) electrodes to reveal the interplay between electronic structure catalytic activity glycerol, diols, monohydric In situ electrochemical tests elucidate that CoO/CFP electrode has lower interfacial impedance, higher charge transfer, faster rate, thereby alcohol than /CFP electrode. Especially glycerol oxidation, only requires 1.32 V reach 10 mA cm −2 , potential is 120 mV The can also produce value‐added products such formate, acetate, glycolate with high selectivity efficiency at low energy consumptions from Theoretical calculations further confirm dominant role octahedrally coordinated Co‐O sites in adsorption, activation, C3‐C1 This work sheds light design highly efficient alcohols by populating octahedral crystal structure.

Язык: Английский

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Unlocking Efficient Hydrogen Production: Nucleophilic Oxidation Reactions Coupled with Water Splitting

Advanced Materials, Год журнала: 2024, Номер unknown

Опубликована: Июнь 10, 2024

Abstract Electrocatalytic water splitting driven by sustainable energy is a clean and promising water‐chemical fuel conversion technology for the production of high‐purity green hydrogen. However, sluggish kinetics anodic oxygen evolution reaction (OER) pose challenges large‐scale hydrogen production, limiting its efficiency safety. Recently, OER has been replaced nucleophilic oxidation (NOR) with biomass as substrate coupled (HER), which attracted great interest. Anode NOR offers faster kinetics, generates high‐value products, reduces consumption. By coupling reaction, can be enhanced while yielding products or degrading pollutants. Therefore, NOR‐coupled HER another new electrolytic strategy after significance realizing development global decarbonization. This review explores potential reactions an alternative to delves into mechanisms, guiding future research in production. It assesses different methods, analyzing pathways catalyst effects. Furthermore, it evaluates role electrolyzers industrialized discusses prospects challenges. comprehensive aims advance efficient economical

Язык: Английский

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Strengthening the Synergy between Oxygen Vacancies in Electrocatalysts for Efficient Glycerol Electrooxidation

Advanced Materials, Год журнала: 2024, Номер 36(26)

Опубликована: Апрель 9, 2024

Defect-engineered bimetallic oxides exhibit high potential for the electrolysis of small organic molecules. However, ambiguity in relationship between defect density and electrocatalytic performance makes it challenging to control final products multi-step multi-electron reactions such systems. In this study, controllable kinetics reduction is used maximize oxygen vacancy a Cu─Co oxide nanosheet (CuCo

Язык: Английский

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Heterogeneous Rhodium Single-Atom-Site Catalyst Enables Chemoselective Carbene N–H Bond Insertion

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(15), С. 10847 - 10856

Опубликована: Апрель 7, 2024

Transition-metal-catalyzed carbene insertion reactions of a nitrogen–hydrogen bond have emerged as robust and versatile methods for the construction C–N bonds. While significant progress homogeneous catalytic metal N–H insertions has been achieved, control chemoselectivity in field remains challenging due to high electrophilicity intermediates. Herein, we present an efficient strategy synthesis rhodium single-atom-site catalyst (Rh-SA) that incorporates Rh atom surrounded by three nitrogen atoms one phosphorus doped carbon support. This Rh-SA catalyst, with loading only 0.15 mol %, exhibited exceptional performance heterogeneous various anilines heteroaryl amines combination diazo esters. Importantly, selectively transformed aniline derivatives bearing multiple nucleophilic moieties into single isomers, while popular Rh2(OAc)4 produced mixture overfunctionalized side products. Additionally, similar selectivities set stereoelectronically diverse esters were obtained, highlighting general applicability this catalysis approach. On basis density functional theory calculations, observed selectivity was attributed barriers accelerated proton transfer assisted Overall, investigation metal-catalyzed underscores potential powerful complementary tool organic synthesis.

Язык: Английский

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PtAu alloying-modulated hydroxyl and substrate adsorption for glycerol electrooxidation to C₃ products

Energy & Environmental Science, Год журнала: 2024, Номер 17(12), С. 4205 - 4215

Опубликована: Янв. 1, 2024

A honeycomb-like PtAu alloy catalyst has been developed to modulate the adsorption capacity of OH − species and configuration glycerol on surface for electrocatalytic upgrading C 3 chemicals.

Язык: Английский

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Preparing iron oxide clusters surface modified Co3O4 nanoboxes by chemical vapor deposition as an efficient electrocatalyst for oxygen evolution reaction

Energy storage materials, Год журнала: 2024, Номер 66, С. 103236 - 103236

Опубликована: Янв. 30, 2024

Язык: Английский

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Electroreductive upgradation of biomass into high-value chemicals and energy-intensive biofuels

Green Chemistry, Год журнала: 2024, Номер 26(5), С. 2454 - 2475

Опубликована: Янв. 1, 2024

Recent advances in electroreductive upgradation of biomass to high-value chemicals and energy-intensive biofuels via various transformation routes are showcased.

Язык: Английский

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Valence Engineering via Manganese‐Doping on Cobalt Nitride Nanoarrays for Efficient Electrochemically Paired Glycerol Valorization and H₂ Production

Advanced Functional Materials, Год журнала: 2024, Номер 34(33)

Опубликована: Март 30, 2024

Abstract Integration of more thermodynamically favorable valorization biomass (e.g., glycerol), compared to sluggish oxygen evolution, with H 2 production is great significance for energy‐saving electrosynthesis value‐added chemicals. However, its widespread deployment has been challenged by costly electrocatalysts and large overpotential reaching an industrial‐relevant current density (≥400 mA cm −2 ). Herein, carbon shell‐encapsulated manganese‐doped cobalt nitride nanoarrays immobilizing on nickel foam, denoted Mn‐CoN@C/NF, are crafted via hydrothermal method ammoniation. As a bifunctional electrocatalyst, the Mn‐CoN@C/NF manifests extraordinary activity glycerol oxidation reaction (GOR) ultralow potential 1.37 V (versus RHE) at 400 , in conjunction evolution (HER) low 31 mV 10 . A record high Faradaic efficiency (97.7%) formate GOR delivered 1.35 (vs RHE). Impressively, two‐electrode electrolyzer capitalizing as catalysts reaches 800 1.83 V, delivering electricity‐saving 15.0% pure water splitting. DFT calculations substantiate that Mn species within Mn‐CoN not only optimize hydrogen adsorption kinetics HER, but also elevate Co 3+ active sites’ GOR. This work offers efficient avenue coproduction valuable

Язык: Английский

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Cu Promoted the Dynamic Evolution of Ni-Based Catalysts for Polyethylene Terephthalate Plastic Upcycling

ACS Catalysis, Год журнала: 2024, Номер 14(7), С. 5314 - 5325

Опубликована: Март 26, 2024

Upcycling plastic wastes into value-added chemicals is a promising approach to put end-of-life back their ecocycle. As one of the polyesters that used daily, polyethylene terephthalate (PET) waste employed here as model substrate. Herein, nickel (Ni)-based catalyst was prepared via electrochemically depositing copper (Cu) species on Ni foam (NiCu/NF). The NiCu/NF formed Cu/CuO and Ni/NiO/Ni(OH)2 core–shell structures before electrolysis reconstructed NiOOH CuOOH/Cu(OH)2 active during ethylene glycol (EG) oxidation. After oxidation, Cu evolved more reduced species. An indirect mechanism identified main EG oxidation (EGOR) mechanism. In EGOR, NiCu60s/NF exhibited an optimal Faradaic efficiency (FE, 95.8%) yield rate (0.70 mmol cm–2 h–1) for formate production. Also, over 80% FE achieved when commercial PET powder hydrolysate applied. Furthermore, water bottle substrate electrocatalytic upcycling, pure terephthalic acid (TPA) recovered only after 1 h electrolysis. Lastly, density functional theory (DFT) calculation revealed key role significantly reducing Gibbs free-energy barrier (ΔG) EGOR's rate-determining step (RDS), promoting catalysts' dynamic evolution, facilitating C–C bond cleavage.

Язык: Английский

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