Tailoring Acidic Oxygen Reduction Selectivity on Single-Atom Catalysts via Modification of First and Second Coordination Spheres

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(20), P. 7819 - 7827

Published: May 13, 2021

Product selectivity in multielectron electrocatalytic reactions is crucial to energy conversion efficiency and chemical production. However, a present practical drawback the limited understanding of actual catalytic active sites. Here, using as prototype single-atom catalysts (SACs) acidic oxygen reduction reaction (ORR), we report structure–property relationship show for first time that molecular-level local structure, including second coordination spheres (CSs), rather than individual atoms, synergistically determines response. ORR on Co-SACs can be tailored from four-electron two-electron pathway by modifying (N or/and O coordination) (C–O–C groups) CSs. Using combined theoretical predictions experiments, X-ray absorption fine structure analyses situ infrared spectroscopy, confirm unique change originates structure-dependent shift sites center Co atom O-adjacent C atom. We this optimizes electronic *OOH adsorption behavior give "best" activity >95% H2O2 electrosynthesis.

Language: Английский

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Carbon‐Based Electrocatalysts for Efficient Hydrogen Peroxide Production

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(49)

Published: Sept. 24, 2021

Abstract Hydrogen peroxide (H 2 O ) is an environment‐friendly and efficient oxidant with a wide range of applications in different industries. Recently, the production hydrogen through direct electrosynthesis has attracted widespread research attention, emerged as most promising method to replace traditional energy‐intensive multi‐step anthraquinone process. In ongoing efforts achieve highly large‐scale H , carbon‐based materials have been developed 2e − oxygen reduction reaction catalysts, benefits low cost, abundant availability, optimal performance. This review comprehensively introduces strategies for optimizing toward production, latest advances hybrid catalysts. The active sites influence coordination heteroatom doping on selectivity are extensively analyzed. particular, appropriate design functional groups understanding effect electrolyte pH expected further improve selective efficiency producing via reaction. Methods improving catalytic activity by interface engineering kinetics summarized. Finally, challenges catalysts face before they can be employed commercial‐scale identified, prospects designing novel electrochemical reactors proposed.

Language: Английский

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The Controllable Reconstruction of Bi‐MOFs for Electrochemical CO₂ Reduction through Electrolyte and Potential Mediation

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(33), P. 18178 - 18184

Published: July 9, 2021

Abstract Monitoring and controlling the reconstruction of materials under working conditions is crucial for precise identification active sites, elucidation reaction mechanisms, rational design advanced catalysts. Herein, a Bi‐based metal–organic framework (Bi‐MOF) electrochemical CO 2 reduction selected as case study. In situ Raman spectra combined with ex electron microscopy reveal that intricate Bi‐MOF can be controlled using two steps: 1) electrolyte‐mediated dissociation conversion to Bi O 3 , 2) potential‐mediated Bi. The intentionally reconstructed catalyst exhibits excellent activity, selectivity, durability formate production, unsaturated surface atoms formed during become sites. This work emphasizes significant impact pre‐catalyst provides insight into highly stable electrocatalysts through regulation these processes.

Language: Английский

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Efficient Ammonia Electrosynthesis and Energy Conversion through a Zn‐Nitrate Battery by Iron Doping Engineered Nickel Phosphide Catalyst

Advanced Energy Materials, Journal Year: 2022, Volume and Issue: 12(13)

Published: Feb. 9, 2022

Abstract The electrocatalytic nitrate reduction reaction (NO 3 ‐RR) to ammonia (NH ) offers a promising alternative approach for NH production and nitrate‐based voltaic cells which can deliver both electricity as products, are also highly attractive. However, nitrate‐to‐NH conversion involves proton‐assisted multiple‐electron transfer process with considerable kinetic barrier, underlying the need efficient catalysts NO – RR. A Zn‐nitrate battery is reported enable “killing three birds one stone” strategy energy supply, removal of pollutants iron doped nickel phosphide (Fe/Ni 2 P) RR catalyst electrode. Iron doping induces downshift d‐band center Ni atoms Fermi level, allowing optimization Gibbs free energies intermediates. Fe/Ni P exhibits 94.3% Faradaic efficiency (FE) nearly 100% at –0.4 V vs. reversible hydrogen electrode (RHE). Further applying this electrocatalyst cathode material, novel power density 3.25 mW cm –2 FE 85.0% production. This work enriches application Zn‐based batteries in field electrocatalysis highlights promise bimetal

Language: Английский

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Accessing Organonitrogen Compounds via C–N Coupling in Electrocatalytic CO₂ Reduction

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(47), P. 19630 - 19642

Published: Nov. 17, 2021

Given the limited product variety of electrocatalytic CO2 reduction reactions solely from and H2O as reactants, it is desirable to expand scope by introducing additional reactants that provide elemental diversity. The integration inorganic heteroatom-containing into could, in principle, enable sustainable synthesis valuable products, such organonitrogen compounds, which have widespread applications but typically rely on NH3 derived energy-intensive fossil-fuel-dependent Haber–Bosch process for their industrial-scale production. In this Perspective, research progress toward building C–N bonds N-integrated highlighted, electrosyntheses urea, acetamides, amines are examined standpoints reactivity, catalyst structure, and, most fundamentally, mechanism. Mechanistic discussions coupling these advances emphasized critically evaluated, with aim directing future investigations improving yield broadening reduction.

Language: Английский

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Interfacial Assembly and Applications of Functional Mesoporous Materials

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(23), P. 14349 - 14429

Published: Oct. 5, 2021

Functional mesoporous materials have gained tremendous attention due to their distinctive properties and potential applications. In recent decades, the self-assembly of micelles framework precursors into mesostructures on liquid-solid, liquid-liquid, gas-liquid interface has been explored in construction functional with diverse compositions, morphologies, mesostructures, pore sizes. Compared one-phase solution synthetic approach, introduction a two-phase system changes behaviors between species, leading possibility for on-demand fabrication unique architectures. addition, controlling interfacial tension is critical manipulate process precise synthesis. particular, breakthroughs based concept "monomicelles" assembly mechanism are very promising interesting synthesis control. this review, we highlight strategies, principles, engineering at macroscale, microscale, nanoscale oriented over past 10 years. The applications various fields, including adsorption, separation, sensors, catalysis, energy storage, solar cells, biomedicine, discussed. Finally, also propose remaining challenges, possible directions, opportunities field future outlook.

Language: Английский

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Oxide-Derived Core–Shell Cu@Zn Nanowires for Urea Electrosynthesis from Carbon Dioxide and Nitrate in Water

ACS Nano, Journal Year: 2022, Volume and Issue: 16(6), P. 9095 - 9104

Published: June 3, 2022

Urea electrosynthesis provides an intriguing strategy to improve upon the conventional urea manufacturing technique, which is associated with high energy requirements and environmental pollution. However, electrochemical coupling of NO3– CO2 in H2O prepare under ambient conditions still a major challenge. Herein, self-supported core–shell Cu@Zn nanowires are constructed through electroreduction method exhibit superior performance toward via contaminants as feedstocks. Both 1H NMR spectra liquid chromatography identify production. The optimized yield rate Faradaic efficiency over can reach 7.29 μmol cm–2 h–1 9.28% at −1.02 V vs RHE, respectively. reaction pathway revealed based on intermediates detected situ attenuated total reflection Fourier transform infrared spectroscopy online differential mass spectrometry. combined results theoretical calculations experiments prove that electron transfer from Zn shell Cu core not only facilitate formation *CO *NH2 but also promote these form C–N bonds, leading faradaic product.

Language: Английский

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A NiCo LDH nanosheet array on graphite felt: an efficient 3D electrocatalyst for the oxygen evolution reaction in alkaline media

Inorganic Chemistry Frontiers, Journal Year: 2021, Volume and Issue: 8(12), P. 3162 - 3166

Published: Jan. 1, 2021

A NiCo LDH nanosheet array on graphite felt is an efficient 3D OER catalyst with the need for overpotential of 249 mV to drive 20 mA cm⁻² in 1.0 M KOH.

Language: Английский

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Main-group elements boost electrochemical nitrogen fixation

Chem, Journal Year: 2021, Volume and Issue: 7(12), P. 3232 - 3255

Published: Nov. 9, 2021

Language: Английский

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Coupling Glucose‐Assisted Cu(I)/Cu(II) Redox with Electrochemical Hydrogen Production

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(48)

Published: Sept. 24, 2021

Abstract Water electrolysis is a sustainable technology for hydrogen production since this process can utilize the intermittent electricity generated by renewable energy such as solar, wind, and hydro. However, large‐scale application of restricted high consumption due to large potential gap ( > 1.23 V) between anodic oxygen evolution reaction cathodic (HER). Herein, novel efficient system developed coupling glucose‐assisted Cu(I)/Cu(II) redox with HER. The onset electrooxidation Cu(I) Cu(II) low 0.7 V RHE (vs reversible electrode). In situ Raman spectroscopy, ex X‐ray photoelectron density functional theory calculation demonstrates that glucose in electrolyte reduce into instantaneously via thermocatalysis process, thus completing cycle redox. assembled electrolyzer only requires voltage input 0.92 achieve current 100 mA cm −2 . Consequently, per cubic H 2 produced 2.2 kWh, half value conventional water (4.5 kWh). This work provides promising strategy low‐cost, high‐purity

Language: Английский

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