Recent Advances in Non‐Precious Metal Single‐Atom Electrocatalysts for Oxygen Reduction Reaction in Low‐Temperature Polymer‐Electrolyte Fuel Cells

ChemCatChem, Journal Year: 2023, Volume and Issue: 15(22)

Published: Oct. 9, 2023

Abstract Fuel cells have emerged as a promising clean electrochemical energy technology with great potential in various sectors, including transportation and power generation. However, the high cost scarcity of noble metals currently used to synthesise electrocatalysts for low‐temperature fuel has hindered their widespread commercialisation. In recent decades, development non‐precious metal cathodic oxygen reduction reaction (ORR) gained significant attention. Among those, atomically dispersed active sites, referred single‐atom catalysts (SACs), are gaining more interest. Nanocarbon materials containing single transition atoms coordinated nitrogen ORR both acidic alkaline conditions thus promise be utilised cathode cells. This review article provides an overview advancements utilisation metal‐based SACs proton exchange membrane (PEMFCs) anion (AEMFCs). We highlight main strategies synthetic approaches tailoring properties enhance activity durability. Based on already achieved results, it is evident that indeed could suitable

Language: Английский

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Microwave‐Assisted Rapid Synthesis of MOF‐Based Single‐Atom Ni Catalyst for CO₂ Electroreduction at Ampere‐Level Current

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(10)

Published: Jan. 17, 2024

Carbon-based single-atom catalysts (SACs) have attracted tremendous interest in heterogeneous catalysis. However, the common electric heating techniques to produce carbon-based SACs usually suffer from prolonged time and tedious operations. Herein, a general facile microwave-assisted rapid pyrolysis method is developed afford within 3 min without inert gas protection. The obtained present high porosity comparable carbonization degree those by techniques. Specifically, Ni implanted N-doped carbon (Ni

Language: Английский

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Ferredoxin‐Inspired Design of S‐Synergized Fe–Fe Dual‐Metal Center Catalysts for Enhanced Electrocatalytic Oxygen Reduction Reaction

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(19)

Published: Feb. 12, 2024

Abstract Dual‐metal center catalysts (DMCs) have shown the ability to enhance oxygen reduction reaction (ORR) owing their distinctive structural configurations. However, precise modulation of electronic structure and in‐depth understanding synergistic mechanisms between dual metal sites DMCs at atomic level remain challenging. Herein, mimicking ferredoxin, Fe‐based (Fe 2 N 6 ‐S) are strategically designed fabricated, in which additional Fe S synchronously installed near serve as “dual modulators” for coarse‐ fine‐tuning modulation, respectively. The as‐prepared ‐S catalyst exhibits enhanced ORR activity outstanding Zinc‐air (Zn–air) battery performance compared conventional single site catalysts. theoretical experimental results reveal that introducing second creates a adsorption alters O configuration effectively activates O─O bond, while effect downward shift d‐band center, facilitating release OH*. Additionally, local engineering heteroatom further facilitates formation rate‐determining step OOH*, thus accelerating kinetics.

Language: Английский

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Highly Reversible Zn–Air Batteries Enabled by Tuned Valence Electron and Steric Hindrance on Atomic Fe–N₄–C Sites

Nano Letters, Journal Year: 2024, Volume and Issue: 24(15), P. 4672 - 4681

Published: April 8, 2024

The bifunctional oxygen electrocatalyst is the Achilles' heel of achieving robust reversible Zn–air batteries (ZABs). Herein, durable electrocatalysis in alkaline media realized on atomic Fe–N4–C sites reinforced by NixCo3–xO4 (NixCo3–xO4@Fe1/NC). Compared with that pristine Fe1/NC, stability evolution reaction (OER) increased 10 times and reduction (ORR) performance also improved. steric hindrance alters valence electron at sites, resulting a shorter Fe–N bond enhanced sites. corresponding solid-state ZABs exhibit an ultralong lifespan (>460 h 5 mA cm–2) high rate (from 2 to 50 cm–2). Furthermore, structural NixCo3–xO4@Fe1/NC before after OER ORR as well charge–discharge cycling explored. This work develops efficient strategy for improving possibly other processes.

Language: Английский

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Surface Engineered Single‐atom Systems for Energy Conversion

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(16)

Published: Jan. 10, 2024

Abstract Single‐atom catalysts (SACs) are demonstrated to show exceptional reactivity and selectivity in catalytic reactions by effectively utilizing metal species, making them a favorable choice among the different active materials for energy conversion. However, SACs still early stages of conversion, problems like agglomeration low conversion efficiency hampering their practical applications. Substantial research focus on support modifications, which vital SAC stability due intimate relationship between atoms support. In this review, category supports variety surface engineering strategies employed SA systems summarized, including site (heteroatom doping, vacancy introducing, groups grafting, coordination tunning) structure (size/morphology control, cocatalyst deposition, facet engineering, crystallinity control). Also, merits single‐atom systematically introduced. Highlights comprehensive summary discussions utilization surface‐engineered diversified applications photocatalysis, electrocatalysis, thermocatalysis, devices. At end potential obstacles using field discussed. This review aims guide rational design manipulation target‐specific capitalizing characteristic benefits engineering.

Language: Английский

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Construction of Fe Nanoclusters/Nanoparticles to Engineer FeN₄ Sites on Multichannel Porous Carbon Fibers for Boosting Oxygen Reduction Reaction

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(23)

Published: Jan. 15, 2024

Abstract Fe–N–C catalysts are emerging as promising alternatives to Pt‐based for the oxygen reduction reaction (ORR), while they still suffer from sluggish kinetics due discontented binding affinity between Fe‐N 4 sites and oxygen‐containing intermediates, unsatisfactory stability. Herein, a flexible multichannel carbon fiber membrane immobilized with atomically dispersed neighboring Fe nanoclusters/nanoparticles (FeN ‐Fe NCP @MCF) is synthesized. The optimized geometric electronic structures of atomic brought by adjacent hierarchically porous structure matrix endow FeN @MCF outstanding ORR activity stability, considerably outperforming its counterpart only commercial Pt/C catalyst. Liquid solid‐state zinc–air batteries employing both exhibit durability. Theoretical calculation reveals that nanoclusters can trigger remarkable electron redistribution modulate hybridization central 3 d O 2 p orbitals, facilitating activation molecules optimizing adsorption capacity intermediates on sites, thus accelerating kinetic. This work offers an effective approach constructing coupling have single atoms coexisting efficient catalysis.

Language: Английский

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Electronegativity Matching of Asymmetrically Coordinated Single‐Atom Catalysts for High‐Performance Lithium–Sulfur Batteries

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(19)

Published: March 13, 2024

Abstract Asymmetrically coordinated single‐atom catalysts are attractive for the implementation of high‐performance lithium–sulfur (Li─S) batteries. However, design principle asymmetric coordination that can efficiently promote bidirectional conversion polysulfides has not been fully realized. Herein, a series Co─N 3 X 1 ( refers to F, O, Cl, S, or P) configurations established, and theoretically unravel relative electronegativity value (REV) be used as an index parameter characterizing catalytic activity. By virtue enhanced chemical affinity with sulfur species lowered Li 2 S decomposition, chlorine‐atom‐constructed optimal REV exhibit stronger effect inhibit shuttling. Such REV‐related is termed effect. Following this principle, novel catalyst dominated Cl configuration successfully synthesized through inside‐out thermal reaction strategy modified layer on cathode‐side separator. Interestingly, assembled Li─S batteries quite high rate capacity (804.3 mAh g −1 at 5.0 C), durable cyclability (0.023% decay per cycle), competitive areal (7.0 cm −2 under 7.5 mg loading lean electrolyte). The guideline provided in work gives impetus pursuit highly efficient practical

Language: Английский

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Recent Design Strategies for M‐N‐C Single‐Atom Catalysts in Oxygen Reduction: An Entropy Increase Perspective

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(36)

Published: March 18, 2024

Abstract Recently, a diverse array of novel metal‐nitrogen‐carbon (M‐N‐C) single‐atom catalysts (SACs) have rapidly evolve, particularly in the realm oxygen reduction reaction (ORR). Despite plethora proposed design and improvement strategies for SACs, comprehensive review systematically compiling components M‐N‐C from unified perspective is notably absent. For first time, thorough examination each component conducted, focusing on entropy increase active sites SACs. single M‐N 4 whole system, an implies elevated degree disorder chaos. Broadly, entropy‐increasing modification M (single mental sites) guest groups entails augmentation chaos, with most effective co‐catalytic synergy achieved by establishing multiple through “cocktail effect”. Concerning N (nitrogen other heteroatoms) C (carbon supports), induces heightened disorder, symmetry breaking more likely to drive toward adsorbing molecules attain equilibrium symmetric structure. All these innovative led remarkable ORR activity stability offer guiding criterion future preparation

Language: Английский

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Engineering Co‐N‐Cr Cross‐Interfacial Electron Bridges to Break Activity‐Stability Trade‐Off for Superdurable Bifunctional Single Atom Oxygen Electrocatalysts

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(15)

Published: Jan. 29, 2024

Abstract Atomically dispersed metal‐nitrogen‐carbon (M‐N‐C) catalysts have exhibited encouraging oxygen reduction reaction (ORR) activity. Nevertheless, the insufficient long‐term stability remains a widespread concern owing to inevitable 2‐electron byproducts, H 2 O . Here, we construct Co‐N‐Cr cross‐interfacial electron bridges (CIEBs) via interfacial electronic coupling between Cr 3 and Co‐N‐C, breaking activity‐stability trade‐off. The partially occupied 3d‐orbitals of CIEBs induce rearrangement CoN 4 sites, lowering Co‐OOH* antibonding orbital occupancy accelerating adsorption intermediates. Consequently, suppress two‐electron ORR process approach apex Sabatier volcano plot for four‐electron pathway simultaneously. As proof‐of‐concept, is synthesized by molten salt template method, exhibiting dominant 4‐electron selectively extremely low yield confirmed Damjanovic kinetic analysis. demonstrates impressive bifunctional catalytic activity (▵E=0.70 V) breakthrough durability including 100 % current retention after 10 h continuous operation cycling performance over 1500 Zn‐air battery. hybrid configuration understanding mechanism reported here could shed new light on design superdurable M‐N‐C catalysts.

Language: Английский

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Atomically dispersed Fe-N-C catalyst with densely exposed Fe-N4 active sites for enhanced oxygen reduction reaction

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 485, P. 149529 - 149529

Published: Feb. 12, 2024

Language: Английский

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