Molecular Strain Accelerates Electron Transfer for Enhanced Oxygen Reduction

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

Published: Jan. 17, 2025

Fe-N-C materials are emerging catalysts for replacing precious platinum in the oxygen reduction reaction (ORR) renewable energy conversion. However, their potential is hindered by sluggish ORR kinetics, leading to a high overpotential and impeding efficient Using iron phthalocyanine (FePc) as model catalyst, we elucidate how local strain can enhance performance of Fe-N-Cs. We use density functional theory predict mechanism four-electron water. Several key differences between mechanisms curved flat FePc suggest that molecular accelerates reductive desorption *OH decreasing barrier ∼60 meV. Our theoretical predictions substantiated experimental validation; find strained on single-walled carbon nanotubes attains half-wave (E1/2) 0.952 V versus reversible hydrogen electrode Tafel slope 35.7 mV dec-1, which competitive with best-reported values. also observe 70 change E1/2 dramatically different slopes configurations, agree well calculated energies. When integrated into zinc-air battery, our device affords maximum power 350.6 mW cm-2 mass activity 810 mAh gZn-1 at 10 mA cm-2. results indicate provides compelling tool modulating activities materials.

Language: Английский

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Spin Engineering of Fe─N─C by Axial Ligand Modulation for Enhanced Bifunctional Oxygen Catalysis

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

Published: Aug. 17, 2024

Abstract Iron‐based single‐atom catalysts (Fe─N─C) exhibit excellent oxygen reduction activity but struggle with bifunctional performance due to their poor evolution activity. Although the Fe spin state is found be closely associated enhanced activity, controllably regulating remains a challenge. Here, controllable regulation of directly achieved through competitive coordination between chlorine and pyridine nitrogen in axial direction Fe─N 4 . The regulated from high intermediate by modulation ligands weak‐field ligand strong‐field pyridinic nitrogen, which leads N─FeN small potential gap (Δ E = 0.68 V). Theoretical calculations indicate that turning accompanied an binding strength sites *OH leading significant decrease OER barrier. Moreover, exhibits sufficient durability for reaction (ORR) (over 50 h), (OER) 200 assembled zinc–air battery 1000 h). Here novel approach proposed designing efficient based on profound insights into Fe─N─C catalysis.

Language: Английский

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Tuning the spin state of the iron center by FePc/Mg(OH)2 heterojunction boosting oxygen reduction performance

Journal of Colloid and Interface Science, Journal Year: 2025, Volume and Issue: 684, P. 690 - 695

Published: Jan. 10, 2025

Language: Английский

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Star-shaped ZIF-derived carbon-based electrocatalysts with FeNX active sites for enhanced oxygen reduction reaction in high-performance zinc-air batteries

Journal of Electroanalytical Chemistry, Journal Year: 2025, Volume and Issue: unknown, P. 118991 - 118991

Published: Feb. 1, 2025

Language: Английский

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Enhanced oxygen reduction reaction using polyoxometalates as mediators in near neutral electrolytes for zinc-air batteries

Electrochimica Acta, Journal Year: 2025, Volume and Issue: unknown, P. 146180 - 146180

Published: April 1, 2025

Language: Английский

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Porphyrin-Based Covalent Organic Framework Encapsulating Multiwalled Carbon Nanotubes: A High-Performance Electrocatalyst for Oxygen Reduction Reaction

Langmuir, Journal Year: 2025, Volume and Issue: unknown

Published: April 17, 2025

The development of efficient and cost-effective oxygen reduction reaction (ORR) catalysts is crucial for advancing fuel cell technologies, given the limitations platinum-based catalysts. Here, we present a novel nanocomposite, cobalt-based porphyrinic covalent organic framework wrapped on multiwalled carbon nanotubes (Co-pCOF@MWCNTs), synthesized via template-directed in situ polymerization. This composite combines high porosity tunable catalytic properties COFs with excellent electrical conductivity MWCNTs. Co-pCOF@MWCNT demonstrates superior ORR activity, exhibiting an onset potential (Eonset) 0.86 V vs RHE 0.1 M KOH, surpassing performance its individual components (Co-pCOF MWCNT) other related materials. enhanced efficiency attributed to synergistic interactions between conductive MWCNT scaffold active COF nanolayers, which facilitate charge transfer increase site exposure. Furthermore, nanocomposite exhibits stability methanol tolerance, establishing as cathodic material cells. work highlights promise integrating materials opens new avenues design advanced energy conversion applications.

Language: Английский

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High yielding hierarchical porous Fe-N-C with enriched effective active sites: Promoting oxygen reduction reaction electrocatalytic kinetics

Science China Technological Sciences, Journal Year: 2025, Volume and Issue: 68(5)

Published: April 17, 2025

Language: Английский

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Covalently anchoring phosphorus nitride imide on carbon nanotubes for efficient electrochemical extraction of uranium

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: unknown, P. 156076 - 156076

Published: Sept. 1, 2024

Language: Английский

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Triphenylphosphine Oxide: A Versatile Covalent Functionality for Carbon Nanotubes

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(46)

Published: Aug. 1, 2024

Abstract Broadening the scope of functionalities that can be covalently bound to single‐walled carbon nanotubes (SWCNTs) is crucial for enhancing versatility this promising nanomaterial class in applied settings. Here we report covalent linkage triphenylphosphine oxide [Ph 3 P(O)] SWCNTs, a hitherto overlooked surface functionality. We detail synthesis and structural characterization new family phosphine oxide‐functionalized diaryliodonium salts facilitate direct Ph P(O) transfer afford novel SWCNTs with tunable content ( SWCNT‐P ). The molecularly‐distributed robust nature attachment was supported by combination methods including Raman, infrared, UV/Vis‐NIR X‐ray photoelectron spectroscopies coupled thermogravimetric analysis. Electron microscopy further revealed effectiveness moiety de‐bundling yield superior dispersibility processability. Finally, electrochemical studies established sensitive presence Li + , Na K wherein Gutmann‐Beckett Lewis acidity parameters ions were quantitatively transduced responses. This work hence presents synthetic, structural, spectroscopic foundation phosphorus‐enriched responsive platform featuring

Language: Английский

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Porphyrin-Confined Supported Ultrasmall Ir Clusters as Oxygen Evolution Catalysts for Water Electrolysis

Inorganic Chemistry, Journal Year: 2024, Volume and Issue: 63(42), P. 19798 - 19808

Published: Oct. 11, 2024

Metalloporphyrin ligands themselves can participate in the redox process, making them beneficial promoting multielectron catalytic process of oxygen evolution reaction (OER). However, OER catalysts synthesized by traditional chemical strategies face challenges water electrolysis. We high-performance and stable alkaline acidic electrocatalysts loaded with ultrasmall iridium clusters taking advantage attraction confinement Ir atoms Ir–N bonds formed porphyrin cavity. The N cavity forms an bond so that carries a negative charge attracts to form above adjust electronic structure clusters. resulting catalyst Tpyp-Ir(IrOX) exhibits small overpotential (242 259 mV) at current density 10 mA cm–2 conditions demonstrates good long-term operational stability. In addition, higher transition frequency (TOF) (1.69 O2 s–1 300 1 M KOH, which is 7 times Ir/C.

Language: Английский

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