High‐Density Atomic Fe–N₄/C in Tubular, Biomass‐Derived, Nitrogen‐Rich Porous Carbon as Air‐Electrodes for Flexible Zn–Air Batteries

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(20)

Published: Feb. 22, 2023

Abstract Developing low‐cost single‐atom catalysts (SACs) with high‐density active sites for oxygen reduction/evolution reactions (ORR/OER) are desirable to promote the performance and application of metal–air batteries. Herein, Fe nanoparticles precisely regulated single atoms supported on waste biomass corn silk (CS) based porous carbon ORR OER. The distinct hierarchical structure hollow tube morphology critical boosting ORR/OER through exposing more accessible sites, providing facile electron conductivity, facilitating mass transfer reactant. Moreover, enhanced intrinsic activity is mainly ascribed high (4.3 wt.%) loading content in as‐synthesized catalyst.Moreover, ultra‐high N doping (10 can compensate insufficient OER conventional FeNC catalysts. When as‐prepared assembled as air‐electrodes flexible Zn–air batteries, they perform a peak power density 101 mW cm −2 , stable discharge–charge voltage gap 0.73 V >44 h, which shows great potential Zinc–air battery. This work provides an avenue transform renewable materials into bifunctional electrocatalysts structure.

Language: Английский

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Promoting Oxygen Reduction Reaction on Atomically Dispersed Fe Sites via Establishing Hydrogen Bonding with the Neighboring P Atoms

Advanced Energy Materials, Journal Year: 2022, Volume and Issue: 13(5)

Published: Dec. 16, 2022

Abstract Single atom catalysts (SACs) comprised of nitrogen‐coordinated transition metal (TM–N–C) moieties show encouraging performance towards the oxygen reduction reaction (ORR). Nevertheless, for reactions involving multiple intermediates, single‐atom sites fail to satisfactorily optimize adsorption all intermediates. Here, a facile strategy is reported construct Fe, P dual‐atom in multimodal porous carbon (Fe,P‐DAS@MPC), and its superiority synergistically boosting ORR demonstrated. Fe,P‐DAS@MPC exhibits excellent with substantially positive onset potential ( E = 1.02 V) half‐wave 1/2 0.92 V). Theoretical analysis unveils cooperative effect composed adjacent Fe atoms, aiding hydrogen bonding interaction can promote adsorption/desorption Additionally, Zn–air battery based on shows high peak power density exceptional cycling stability. These findings provide novel avenue design electrocatalysts practical energy conversion applications.

Language: Английский

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Co(CN)3 catalysts with well-defined coordination structure for the oxygen reduction reaction

Nature Catalysis, Journal Year: 2023, Volume and Issue: 6(12), P. 1164 - 1173

Published: Nov. 16, 2023

Language: Английский

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Development of SnCo2O4 spinel supported on the rGO nanosheet with the improved electrochemical performance of OER activity

International Journal of Hydrogen Energy, Journal Year: 2023, Volume and Issue: 51, P. 436 - 447

Published: July 11, 2023

Language: Английский

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Vacancy Defects Inductive Effect of Asymmetrically Coordinated Single‐Atom Fe─N₃S₁ Active Sites for Robust Electrocatalytic Oxygen Reduction with High Turnover Frequency and Mass Activity

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(11)

Published: Dec. 16, 2023

Abstract The development of facile, efficient synthesis method to construct low‐cost and high‐performance single‐atom catalysts (SACs) for oxygen reduction reaction (ORR) is extremely important, yet still challenging. Herein, an atomically dispersed N, S co‐doped carbon with abundant vacancy defects (NSC‐vd) anchored Fe single atoms (SAs) reported a inductive effect proposed promoting electrocatalytic ORR. optimized catalyst featured stable Fe─N 3 1 active sites exhibits excellent ORR activity high turnover frequency mass activity. In situ Raman, attenuated total reflectance surface enhanced infrared absorption spectroscopy reveal the exhibit different kinetic mechanisms in acidic alkaline solutions. Operando X‐ray spectra SAs/NSC‐vd electrolyte closely related coordination structure. Theoretical calculation reveals upshifted d band center facilitates adsorption O 2 accelerates kinetics process *OH reduction. around balance OOH* formation reduction, thus synergetically process.

Language: Английский

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Atomically Dispersed Fe Sites Regulated by Adjacent Single Co Atoms Anchored on N‐P Co‐Doped Carbon Structures for Highly Efficient Oxygen Reduction Reaction

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(17)

Published: July 27, 2023

Abstract Manipulating the coordination environment and electron distribution for heterogeneous catalysts at atomic level is an effective strategy to improve electrocatalytic performance but remains challenging. Herein, atomically dispersed Fe Co anchored on nitrogen, phosphorus co‐doped carbon hollow nanorod structures (FeCo‐NPC) are rationally designed synthesized. The as‐prepared FeCo‐NPC catalyst exhibits significantly boosted kinetics greatly upshifts half‐wave potential oxygen reduction reaction. Furthermore, when utilized as cathode, also displays excellent zinc‐air battery performance. Experimental theoretical results demonstrate that introduction of single atoms with Co‐N/P around isolated induces asymmetric distribution, resulting in suitable adsorption/desorption ability intermediates optimized reaction barrier, thereby improving activity.

Language: Английский

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Epoxy‐rich Fe Single Atom Sites Boost Oxygen Reduction Electrocatalysis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(36)

Published: July 15, 2023

Electrocatalysts for highly efficient oxygen reduction reaction (ORR) are crucial energy conversion and storage devices. Single-atom catalysts with maximized metal utilization altered electronic structure the most promising alternatives to replace current benchmark precious metals. However, atomic level understanding of functional role each species at anchoring sites is still unclear poorly elucidated. Herein, we report Fe single atom sulfur groups near atomically dispersed centers (Fe1/NSOC) ORR. The Fe1/NSOC delivers a half-wave potential 0.92 V vs. RHE, which much better than those commercial Pt/C (0.88 V), atoms on N-doped carbon (Fe1/NC, 0.89 V) reported nonprecious catalysts. spectroscopic measurements reveal that presence group induces formation epoxy FeN4S2 centers, not only modulate but also participate catalytic process improve kinetics. density theory calculations demonstrate existence engineer charges reactive center facilitate reductive release OH* (rate-limiting step), thus boosting overall efficiency.

Language: Английский

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State-of-the-art single-atom catalysts in electrocatalysis: From fundamentals to applications

Nano Energy, Journal Year: 2023, Volume and Issue: 113, P. 108570 - 108570

Published: May 29, 2023

Language: Английский

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Decoration of NiFe‐LDH Nanodots Endows Lower Fe‐ d Band Center of Fe ₁ ‐N‐C Hollow Nanorods as Bifunctional Oxygen Electrocatalysts with Small Overpotential Gap

Advanced Energy Materials, Journal Year: 2023, Volume and Issue: 13(13)

Published: Feb. 2, 2023

Abstract Single‐atom Fe‐N‐C (denoted as Fe 1 ‐N‐C) catalysts exhibit inadequate bifunctional activities to conquer the sluggish oxygen reduction and evolution reaction (ORR/OER), hindering their practical applications in rechargeable Zn‐air batteries (ZABs). Here, by employing ‐N‐C hollow nanorods ORR‐active support, OER‐active NiFe‐layered double hydroxide (NiFe‐LDH) nanodots are evenly decorated through a spatially confined process form NiFe‐LDH/Fe heterostructure with abundant accessible catalytic sites. The not only enhances ORR activity of pristine but also realizes efficient ORR/OER one monolithic catalyst. Theoretical calculations reveal that introducing NiFe‐LDH results donation electrons matrix thus lowers Fe‐ d band center Fe‐N 4 sites, dramatically narrowing energy barriers rate‐limiting steps. As result, deliver remarkable half‐wave potential 0.90 V versus reversible hydrogen electrode, surpassing bare commercial Pt/C. Impressively, integrated show outstanding performance small overpotential gap 0.65 V. liquid‐state ZABs an air‐cathode catalyst peak power density 205 mW cm −2 long‐term cycling stability up 400 h.

Language: Английский

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Modulating Electronic Structures of Iron Clusters through Orbital Rehybridization by Adjacent Single Copper Sites for Efficient Oxygen Reduction

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(39)

Published: July 24, 2023

The atom-cluster interaction has recently been exploited as an effective way to increase the performance of metal-nitrogen-carbon catalysts for oxygen reduction reaction (ORR). However, rational design such and understanding their structure-property correlations remain a great challenge. Herein, we demonstrate that introduction adjacent metal (M)-N4 single atoms (SAs) could significantly improve ORR well-screened Fe atomic cluster (AC) catalyst by combining density functional theory (DFT) calculations experimental analysis. DFT studies suggest Cu-N4 SAs act modulator assist O2 adsorption cleavage O-O bond on AC active center, well optimize release OH* intermediates accelerate whole kinetic. depositing with nitrogen doped mesoporous carbon nanosheet are then constructed through universal interfacial monomicelles assembly strategy. Consistent theoretical predictions, resultant exhibits outstanding half-wave potential 0.92 eV in alkali 0.80 acid, high power 214.8 mW cm-2 zinc air battery. This work provides novel strategy precisely tuning atomically dispersed poly-metallic centers electrocatalysis.

Language: Английский

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