Electrochemical Oxidation of Small Molecules for Energy‐Saving Hydrogen Production

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(30)

Published: May 27, 2024

Abstract Electrochemical water splitting is a promising technique for the production of high‐purity hydrogen. Substituting slow anodic oxygen evolution reaction with an oxidation that thermodynamically more favorable enables energy‐efficient Moreover, this approach facilitates degradation environmental pollutants and synthesis value‐added chemicals through rational selection small molecules as substrates. Strategies small‐molecule electrocatalyst design are critical to electrocatalytic performance, focus on achieving high current density, selectivity, Faradaic efficiency, operational durability. This perspective discusses key factors required further advancement, including technoeconomic analysis, new reactor system design, meeting requirements industrial applications, bridging gap between fundamental research practical product detection separation. aims advance development hybrid electrolysis applications.

Language: Английский

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Recent Advances and Perspectives on Coupled Water Electrolysis for Energy‐Saving Hydrogen Production

Advanced Science, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 7, 2025

Abstract Overall water splitting (OWS) to produce hydrogen has attracted large attention in recent years due its ecological‐friendliness and sustainability. However, the efficiency of OWS been forced by sluggish kinetics four‐electron oxygen evolution reaction (OER). The replacement OER alternative electrooxidation small molecules with more thermodynamically favorable potentials may fundamentally break limitation achieve production low energy consumption, which also be accompanied value‐added chemicals than or electrochemical degradation pollutants. This review critically assesses latest discoveries coupled various OWS, including alcohols, aldehydes, amides, urea, hydrazine, etc. Emphasis is placed on corresponding electrocatalyst design related mechanisms (e.g., dual hydrogenation N–N bond breaking hydrazine C═N regulation urea inhibit hazardous NCO − NO productions, etc.), along emerging reactions (electrooxidation tetrazoles, furazans, iodide, quinolines, ascorbic acid, sterol, trimethylamine, etc.). Some new decoupled electrolysis self‐powered systems are discussed detail. Finally, potential challenges prospects highlighted aid future research directions.

Language: Английский

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Hollow Mo/MoS_Vn Nanoreactors with Tunable Built‐in Electric Fields for Sustainable Hydrogen Production

Advanced Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 8, 2024

Abstract Constructing built‐in electric field (BIEF) in heterojunction catalyst is an effective way to optimize adsorption/desorption of reaction intermediates, while its precise tailor achieve efficient bifunctional electrocatalysis remains great challenge. Herein, the hollow Mo/MoS Vn nanoreactors with tunable BIEFs are elaborately prepared simultaneously promote hydrogen evolution (HER) and urea oxidation (UOR) for sustainable production. The BIEF induced by sulfur vacancies can be modulated from 0.79 0.57 0.42 mV nm −1 , exhibits a parabola‐shaped relationship HER UOR activities, V1 nanoreactor moderate presents best activity. Theoretical calculations reveal that evidently facilitate breakage N─H bond UOR. electrolyzer assembled delivers cell voltage 1.49 V at 100 mA cm −2 which 437 lower than traditional water electrolysis, also excellent durability 200 h. Life cycle assessment indicates HER||UOR system possesses notable superiority across various environment impact energy consumption. This work provide theoretical experimental direction on rational design advanced materials energy‐saving eco‐friendly

Language: Английский

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Local Charge Modulation Induced the Formation of High‐Valent Nickel Sites for Enhanced Urea Electrolysis

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(41)

Published: Aug. 17, 2024

Abstract Ni‐based electrocatalysts are considered to be significantly promising candidates for electrocatalytic urea oxidation reaction (UOR). However, their UOR activity and stability severely enslaved by the inevitable Ni group self‐oxidation phenomenon. In this study, glassy state NiFe LDH with uniform Cu dopant (Cu‐NiFe LDH) a simple sol–gel strategy is successfully synthesized. When served as catalyst, Cu‐NiFe required 123 mV lower potential at both 10 100 mA cm −2 in comparison conventional anodic OER. It can also operate steadily more than 300 h . The in‐depth investigation reveals that incorporation optimize local electronic structure of species induce high‐valent sites. sites would act active center during proposed energetically favorable route, which directly reacts on without inducing formation NiOOH species, resulting boosted stability.

Language: Английский

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Revealing the reactant adsorption role of high-valence WO3 for boosting urea-assisted water splitting

Chinese Journal of Structural Chemistry, Journal Year: 2025, Volume and Issue: unknown, P. 100519 - 100519

Published: Jan. 1, 2025

Language: Английский

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Co₂P-NiMoN/NF Heterostructure Nanorod Arrays as Efficient Bifunctional Electrocatalysts for Urea Electrolysis

ACS Applied Materials & Interfaces, Journal Year: 2025, Volume and Issue: unknown

Published: March 4, 2025

Electrolysis of water represents an effective method for the generation high-purity hydrogen. Nevertheless, anodic oxygen evolution reaction (OER) exhibits slow kinetics, which leads to a high electrolytic potential and induces excessive energy consumption. In this work, nickel foam-supported 3D phosphide/bimetal nitride (Co2P-NiMoN/NF) nanorod array catalyst is prepared by calcination NiMoO4, followed phosphatization Co(OH)2. The heterostructure excellent catalytic activity cathodic hydrogen (HER: η100 = 98 mV, η1000 297 mV) OER (η100 277 382 electrolysis in alkaline electrolyte, indicating its feasibility as bifunctional overall splitting (OWS). Additionally, at current density 100 mA cm-2, associated oxidation decreased roughly 160 mV when replaced with urea process (UOR), has far lower thermodynamic equilibrium potential. Density functional theory (DFT) calculations reveal that heterointerface between Co2P NiMoN enriches electronic states near Fermi level, thereby enhancing electron transfer promoting charge redistribution. This modulation precisely tunes adsorption strengths reactants during process, ultimately boosting electrocatalytic performance. A cm-2 can be attained cell voltage 1.51 V Co2P-NiMoN/NF used anode cathode cell. Notably, significantly compared (1.65 V), well previously published values. findings demonstrate efficient strategy energy-efficient production through substituting UOR electrolysis.

Language: Английский

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Electrochemical N–N Oxidatively Coupled Dehydrogenation of 3,5-Diamino-1H-1,2,4-triazole for Value-Added Chemicals and Bipolar Hydrogen Production

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: March 8, 2025

Electrochemical H2 production from water favors low-voltage molecular oxidation to replace the oxygen evolution reaction as an energy-saving and value-added approach. However, there exists a mismatch between high demand for slow anodic reactions, restricting practical applications of such hybrid systems. Here, we propose bipolar approach, with generation N–N oxidatively coupled dehydrogenation (OCD) 3,5-diamino-1H-1,2,4-triazole (DAT), in addition cathodic generation. The system requires relatively low potentials 0.872 1.108 V vs RHE reach 10 500 mA cm–2, respectively. H-type electrolyzer only 0.946 1.129 deliver 100 respectively, electricity consumption (1.3 kWh per m3 H2) reduced by 68%, compared conventional splitting. Moreover, process is highly appealing due absence traditional hazardous synthetic conditions azo compounds at anode crossover/mixing H2/O2 electrolyzer. A flow-type operates stably cm–2 300 h. Mechanistic studies reveal that Pt single atom nanoparticle (Pt1,n) optimize adsorption S active sites over Pt1,n@VS2 catalysts. At anode, stepwise −NH2 DAT then oxidative coupling −N–N– predominantly form while generating H2. present report paves new way atom-economical aminotriazole green electrosynthesis chemicals.

Language: Английский

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Cutting‐Edge Optimization Strategies and In Situ Characterization Techniques for Urea Oxidation Reaction Catalysts: A Comprehensive Review

Advanced Energy Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 10, 2025

Abstract Urea electrolysis presents an eco‐friendly, cost‐effective method for hydrogen (H 2 ) production and pollution control. However, its efficiency is limited by a slow 6‐electron transfer process, necessitating advanced electrocatalysts to accelerate the urea oxidation reaction (UOR) moderate overpotential, thereby cutting energy losses. Developing efficient, affordable vital practical (UE) improving UOR kinetics. Optimizing requires creating highly active sites, enhancing electrical conductivity, manipulating electronic structures improved electron intermediate binding affinities. This review explores recent advances in catalyst design, focusing on transition metal‐based catalysts, including nanostructures, phases, defects, heterostructures, alloys, composites. It underscores importance of understanding structure‐performance relationships, surface reconstruction phenomena, mechanisms through situ characterization. Additionally, it critically assesses challenges catalysis provides insights developing high‐performance electrocatalysts. The finishes with perspectives future research directions green generation via electrolysis.

Language: Английский

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^*H Species Regulation of Heterostructured Cu₂O/NiO Nanoflowers Boosting Tandem Nitrite Reduction for High‐Efficiency Ammonia Production

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 18, 2025

Abstract Ambient electrocatalytic reduction of NO 2 − to NH 3 (NO RR) provides a reliable route for migrating pollutants and simultaneously generating valuable 3. However, the RR involves multistep electron transfer complex intermediates, rendering achievement high selectivity major challenge. In this contribution, heterostructured Cu O/NiO nanoflowers are explored incorporating advantages dual active sites as highly selective catalyst. Combined theoretical calculations in situ FTIR/EPR spectroscopy analysis, it is revealed synergistic effect O NiO promote energetics heterostructure electrocatalyst through tandem catalysis pathway, where activates initial absorption deoxygenation boosting * formation, while generated on then transferred substrate with abundant hydrogen conversion. Moreover, formation enhances H retention capacity, promoting consumed inhibiting inter‐ species binding. As result, equipped flow cell displays superior yield rate 128.2 mg h −1 cm −2 Faradaic efficiency 97.1% at current density −1.25 A . Further, designed system proven be adaptable other electrochemical production reactions including reduction.

Language: Английский

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Electron Shuttling of Iron‐Oxygen‐Cobalt Bridging in Cobalt Assembled Iron Oxyhydroxide Catalyst Boosts the Urea Oxidation Stability and Activity

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 21, 2025

Abstract Iron (Fe)‐based materials hold great potential as urea oxidation reaction (UOR) catalysts, however, the deactivation of active Fe‐oxyhydroxide (FeOOH) species induced by its dissolution during catalytic process under high current densities is still significant challenge. Herein, cobalt (Co) assembled FeOOH constructed, and formation Iron‐Oxygen‐Cobalt (Fe‐O‐Co) bridging triggers electron transfer from Co to Fe sites. This shuttling induces low valence state sites in FeOOH. Co‐FeOOH catalyst achieves a density 1000 mA cm −2 at voltage merely 1.59 V, showing substantial improvement compared pure (1.97 V). Meanwhile, urea‐assisted anion exchange membrane electrolyzer, after 24 h continuous operation , fluctuation 12.4%, significantly lower than that (49.9%). The situ experiments theoretical calculations demonstrate Fe‐O‐Co endows suppressive Fe‐segregation, fast charge Fe(Co)OOH phase negative‐shifted d‐band center metal sites, boosting UOR stability activity.

Language: Английский

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