Single-Atom Ni Anchored on α-MnO₂ Nanorods as an Electrocatalyst for the Oxygen Evolution and Oxygen Reduction Reactions

ACS Applied Nano Materials, Journal Year: 2024, Volume and Issue: 7(15), P. 18027 - 18035

Published: July 30, 2024

Developing efficient MnO2-based bifunctional catalysts is a considerable challenge due to slow oxygen reduction reaction (ORR) kinetics and the limited activity of evolution (OER). Herein, an catalyst Ni/α-MnO2 prepared by straightforward solid-phase synthesis method, enabling anchoring Ni atoms onto α-MnO2 surface. The electrochemically active surface area significantly enhanced generation vacancies presence atomic sites. After decoration, half-wave potential ORR elevated 0.82 V, while overpotential for OER reduced 366 mV, resulting in exceptionally low overall (ΔE = 0.79 V). Density functional theory calculations reveal that d-band center Mn exhibits negative shifts, consequently lowering energy barrier conversion OOH* O* OH* OER. In secondary zinc–air battery, supreme power density 290 mW cm–2 acquired at current 350 mA cm–2, surpassing performance pristine α-MnO2. This work offers valuable guidance development high-performance catalysts.

Language: Английский

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Regulating the Water Dissociation on Atomic Iron Sites to Speed Up CO₂ Protonation and Achieve pH‐Universal CO₂ Electroreduction

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(40)

Published: Aug. 22, 2024

Abstract Atomic Fe sites enabled electrochemical carbon dioxide (CO 2 ) reduction (ECO R) to monoxide (CO) at low overpotentials. However, the narrow potential ranges for selective CO conversion on atomic hindered production high current densities. Therefore, unveiling electroreduction processes and clarifying catalytic mechanisms different are important better design of catalysts toward efficient ECO R. Herein, R single‐atom, dual‐atom, cluster systematically investigated, clarify that balanced water dissociation protonation dual‐atom promote production. The catalyst achieves Faradaic efficiencies ( FE above 92% over a wide range −0.4–−0.9 V versus reversible hydrogen electrode maintains 91% after 153‐h electrolysis in H‐type cell. Benefitting from favorable sites, pH‐universal is achieved alkali‐/acid‐/bicarbonate‐fed membrane assembly electrolyzer, with exceeds 98% strongly acidic/alkaline neutral mediums. work reveals dissociation‐promoted presents feasible regulation highly active/selective

Language: Английский

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Regulating the Electronic Configuration of Single-Atom Catalysts with Fe–N₅ Sites via Environmental Sulfur Atom Doping for an Enhanced Oxygen Reduction Reaction

ACS Sustainable Chemistry & Engineering, Journal Year: 2024, Volume and Issue: 12(29), P. 11033 - 11043

Published: July 11, 2024

Language: Английский

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Intrinsic Electron Transfer in Heteronuclear Dual‐Atom Sites Facilitates Selective Electrocatalytic Carbon Dioxide Reduction

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

Published: Sept. 30, 2024

Abstract The metal–metal (M 1 –M 2 ) interactions in heteronuclear dual‐atom catalysts (HNDACs) significantly optimize the electronic properties of active sites, resulting promotion reaction kinetics electrocatalysis. However, regulation mechanisms these M sites still remain unclear. Herein, intrinsic electron transfer Fe–Zn are revealed for facilitating electrocatalytic carbon dioxide reduction (ECO R) to monoxide (CO). electronegativity difference between Fe and Zn centers induces specific from Fe, which regulates structures leading optimized pathway CO ‐to‐CO conversion on sites. HNDAC (FeZnNC) exhibits superior ECO R performances than single‐atom Fe/Zn (FeNC ZnNC) typical H‐cell system, maximum partial current density FeZnNC reaches more 3.3 1.8 folds those FeNC ZnNC, respectively. More importantly, a strongly acidic medium (pH = 1), achieves Faradaic efficiencies greater 94% range 100–400 mA cm −2 . This work uncovers at diatomic providing new insights rational design high‐performance HNDACs toward industrial

Language: Английский

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Core‐Shell Quantum Wires‐Supported Single‐Atom Fe Electrocatalysts for Efficient Overall Water Splitting

Small, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 12, 2024

It is of great significance for the development hydrogen energy technology by exploring new-type and high-efficiency electrocatalysts (such as single atom catalysts (SACs)) water splitting. In this paper, combining interface engineering doping engineering, a unique iron (Fe)-doped carbon-coated nickel sulfide (Ni

Language: Английский

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