Efficient Proton-exchange Membrane Fuel Cell Performance of Atomic Fe Sites via p–d Hybridization with Al Dopants

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(18), P. 12636 - 12644

Published: April 27, 2024

Orbital hybridization to regulate the electronic structures and surface chemisorption properties of transition metals is great importance for boosting oxygen reduction reaction (ORR) in proton-exchange membrane fuel cells (PEMFCs). Herein, we developed a core–shell rambutan-like nanocarbon catalyst (FeAl-RNC) with atomically dispersed Fe–Al atom pairs from metal–organic framework (MOF) material. Experimental theoretical results demonstrate that strong p–d orbital between Al Fe an asymmetric electron distribution moderate adsorption strength intermediates, rendering enhanced intrinsic ORR activity. Additionally, structure FeAl-RNC abundant micropores macropores can enhance density active sites, stability, transport pathways PEMFC. The FeAl-RNC-based PEMFC achieves excellent activity (68.4 mA cm–2 at 0.9 V), high peak power (1.05 W cm–2), good stability only 7% current loss after 100 h 0.7 V under H2–O2 condition.

Language: Английский

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Fe/Cu diatomic sites dispersed on nitrogen-doped mesoporous carbon for the boosted oxygen reduction reaction in Mg-air and Zn-air batteries

Applied Catalysis B Environment and Energy, Journal Year: 2024, Volume and Issue: 358, P. 124450 - 124450

Published: July 27, 2024

Language: Английский

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Carbazole-Based branched Poly(Aryl Piperidinium) membranes for Ultra-Stable anion exchange membrane fuel cells

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 489, P. 151446 - 151446

Published: April 18, 2024

Language: Английский

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Constructing Asymmetric Fe–Nb Diatomic Sites to Enhance ORR Activity and Durability

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 12, 2024

Iron-nitrogen-carbon (Fe-N-C) materials have been identified as a promising class of platinum (Pt)-free catalysts for the oxygen reduction reaction (ORR). However, dissolution and oxidation Fe atoms severely restrict their long-term stability performance. Modulating active microstructure Fe-N-C is feasible strategy to enhance ORR activity stability. Compared with common 3d transition metals (Co, Ni, etc.), 4d metal atom Nb has fewer d electrons more unoccupied orbitals, which could potentially forge robust interaction site optimize binding energy oxygen-containing intermediates while maintaining Herein, an asymmetric Fe-Nb diatomic catalyst (FeNb/c-SNC) was synthesized, exhibited superior performance compared those single-atom (SACs). The strong within sites optimized desorption key (*OH), so that adsorption Fe-*OH approaches apex volcano plot, thus exhibiting optimal activity. More importantly, introducing effectively strengthen Fe-N bonding suppress demetalation, causing outstanding zinc-air battery (ZAB) hydroxide exchange membrane fuel cell (HEMFC) equipped our FeNb/c-SNC deliver high peak power densities 314 mW cm

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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Precisely constructing charge-asymmetric dual-atom Fe sites supported on hollow porous carbon spheres for efficient oxygen reduction

Energy & Environmental Science, Journal Year: 2024, Volume and Issue: 17(13), P. 4646 - 4657

Published: Jan. 1, 2024

Transition group metal catalysts showing atomic dispersion are on the rise as affordable electrocatalysts for oxygen reduction reaction (ORR) in fuel cell batteries, but their activity acidic media remains constrained.

Language: Английский

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Precisely designing asymmetrical selenium-based dual-atom sites for efficient oxygen reduction

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 7, 2025

Owing to their synergistic interactions, dual-atom catalysts (DACs) with well-defined active sites are attracting increasing attention. However, more experimental research and theoretical investigations needed further construct explicit understand the synergy that facilitates multistep catalytic reactions. Herein, we precisely design a series of asymmetric selenium-based comprise heteronuclear SeN2–MN2 (M = Fe, Mn, Co, Ni, Cu, Mo, etc.) for efficient oxygen reduction reaction (ORR). Spectroscopic characterisation calculations revealed selenium atoms can efficiently polarise charge distribution other metal through short-range regulation. In addition, compared Se or Fe single-atom sites, SeFe facilitate in conversion energy barrier from *O *OH via coadsorption intermediates. Among these designed catalysts, selenium-iron achieves superior alkaline ORR performance, half-wave potential 0.926 V vs. reversible hydrogen electrode. SeN2–FeN2-based Zn–air battery has high specific capacity (764.8 mAh g−1) maximum power density (287.2 mW cm−2). This work may provide good perspective designing DACs improve efficiency. Dual-atom precise gaining attention, but studies optimise construction synergy. Here authors report dual- atom reaction.

Language: Английский

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Targeting Synthesis of Diatomic Catalysts by Selective Etching and Sequential Adsorption of Metal Atom

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

Published: Jan. 8, 2025

Diatomic catalysts featuring a tunable structure and synergetic effects hold great promise for various reactions. However, their precise construction with specific configurations diverse metal combinations is still challenging. Here, selective etching ion adsorption strategy proposed to accurately assign second atom (M2) geminal the single site (M1–Nx) constructing diatomic sites (e.g., Fe–Pd, Fe–Pt, Fe–Ru, Fe–Zn, Co–Fe, Co–Ni, Co–Cu). In this strategy, hydrogen peroxide selectively etches positively charged carbon atoms near M1–Nx moiety (denoted as α-C) produces vacancy, which could trap M2 at subsequent step. These show optimized electronic enhanced oxygen reduction activity compared single-site counterparts, representative Fe–Pd–NC Co–Fe–NC stand most active reaction (half-wave potential of 0.92 0.91 V, respectively). The α-C in single-atom reported here represents new post-treatment targeting synthesis sites.

Language: Английский

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S‐Block Metal Mg‐Mediated Co─N─C as Efficient Oxygen Electrocatalyst for Durable and Temperature‐Adapted Zn–Air Batteries

Advanced Science, Journal Year: 2024, Volume and Issue: unknown

Published: July 4, 2024

In the quest to enhance Zn-air batteries (ZABs) for operating across a wide spectrum of temperatures, synthesizing robust oxygen electrocatalysts is paramount. Conventional strategies focusing on orbital hybridization d-d and p-d aim moderate excessive interaction between d-band transition metal active site intermediate, yet often yield suboptimal performance. Herein, an innovative s-block modulation reported refine electronic structure catalytic behavior Co─NC catalysts. Employing density functional theory (DFT) calculations, it revealed that incorporating Mg markedly depresses center Co sites, thereby fine-tuning adsorption energy reduction reaction (ORR) intermediate. Consequently, Mg-modified catalyst (MgCo─NC) unveils remarkable intrinsic ORR activity with significantly reduced activation (Ea) 10.0 kJ mol

Language: Английский

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Precise synthesis of dual atom sites for electrocatalysis

Nano Research, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 17, 2024

Language: Английский

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