Unveiling the Proton‐Feeding Effect in Sulfur‐Doped Fe−N−C Single‐Atom Catalyst for Enhanced CO₂ Electroreduction

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(32)

Published: June 8, 2022

Heteroatom-doping in metal-nitrogen-carbon single-atom catalysts (SACs) is considered a powerful strategy to promote the electrocatalytic CO2 reduction reaction (CO2 RR), but origin of enhanced catalytic activity still elusive. Here, we disclose that sulfur doping induces an obvious proton-feeding effect for RR. The model SAC catalyst with second-shell FeN4 (Fe1 -NSC) was verified by X-ray absorption spectroscopy and aberration-corrected scanning transmission electron microscopy. Fe1 -NSC exhibits superior RR performance compared sulfur-free most reported Fe-based SACs, maximum CO Faradaic efficiency 98.6 % turnover frequency 1197 h-1 . Kinetic analysis situ characterizations confirm accelerates H2 O activation feeds sufficient protons promoting conversion *COOH, which also corroborated theoretical results. This work deepens understanding mechanism based on catalysts.

Language: Английский

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Enhanced Dual‐Directional Sulfur Redox via a Biotemplated Single‐Atomic Fe–N₂ Mediator Promises Durable Li–S Batteries

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(28)

Published: May 12, 2022

The lithium-sulfur (Li-S) battery is considered as an appealing candidate for next-generation electrochemical energy storage systems because of high and low cost. Nonetheless, its development plagued by the severe polysulfide shuttling sluggish reaction kinetics. Although single-atom catalysts (SACs) have emerged a promising remedy to expedite sulfur redox chemistry, mediocre loading, inferior atomic utilization, elusive catalytic pathway handicap their practical application. To tackle these concerns, in this work, unsaturated Fe single atoms with loading capacity (≈6.32 wt%) are crafted on 3D hierarchical C3 N4 architecture (3DFeSA-CN) means biotemplated synthesis. By electrokinetic analysis theoretical calculations, it uncovered that 3DFeSA-CN harnesses robust electrocatalytic activity boost dual-directional redox. As result, S@3DFeSA-CN can maintain durable cyclic performance negligible decay rate 0.031% per cycle over 2000 cycles at 1.0 C. More encouragingly, assembled Li-S 5.75 mg cm-2 harvest areal 6.18 mAh . This work offers solution optimize carbonaceous support coordination environment SACs, thereby ultimately elevating pragmatic batteries.

Language: Английский

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Tuning the Coordination Environment of Carbon‐Based Single‐Atom Catalysts via Doping with Multiple Heteroatoms and Their Applications in Electrocatalysis

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(38)

Published: Feb. 13, 2023

Abstract Carbon‐based single‐atom catalysts (SACs) are considered to be a perfect platform for studying the structure–activity relationship of different reactions due adjustability their coordination environment. Multi‐heteroatom doping has been demonstrated as an effective strategy tuning environment carbon‐based SACs and enhancing catalytic performance in electrochemical reactions. Herein, recently developed strategies multi‐heteroatom doping, focusing on regulation active sites by heteroatoms shells, summarized. In addition, correlation between activity investigated through representative experiments theoretical calculations various Finally, concerning certain shortcomings current multi‐heteroatoms, some suggestions put forward promote development field electrocatalysis.

Language: Английский

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A General Strategy for Engineering Single-Metal Sites on 3D Porous N, P Co-Doped Ti₃C₂T_X MXene

ACS Nano, Journal Year: 2022, Volume and Issue: 16(3), P. 4116 - 4125

Published: Feb. 21, 2022

Two-dimensional (2D) MXenes have been developed to stabilize single atoms via various methods, such as vacancy reduction and heteroatom-mediated interactions. However, anchoring on 3D porous further increase catalytic active sites thus construct electrocatalysts with high activity stability remains unexplored. Here, we reported a general synthetic strategy for engineering single-metal N, P codoped Ti3C2TX nanosheets. Through "gelation-and-pyrolysis" process, series of atomically dispersed metal catalysts (Pt, Ir, Ru, Pd, Au) supported by nanosheets structure can be obtained serve efficient the electrochemical hydrogen evolution reaction (HER). As result favorable electronic geometric N(O), P-coordinated optimizing intermediates adsorption exposing surface facilitating charge/mass transfer, as-synthesized Pt SA-PNPM catalyst shows ∼20-fold higher than commercial Pt/C HER over wide pH range.

Language: Английский

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Tuning Co‐Catalytic Sites in Hierarchical Porous N‐Doped Carbon for High‐Performance Rechargeable and Flexible Zn‐Air Battery

Advanced Energy Materials, Journal Year: 2022, Volume and Issue: 13(1)

Published: Nov. 6, 2022

Abstract The strategy of heteroatom doping and metal active sites can synergistically promote oxygen electrocatalysis. Especially, the combination theoretical simulations with experimental results provides new opportunities to understand electrocatalytic mechanism. Herein, 3D carbon nanosheets aggregate highly branched nanotubes cobalt (CoCNTs/PNAs) is prepared via facile self‐assembly‐pyrolysis strategy. CoCNTs/PNAs electrocatalysts exhibit superior bifunctional activities reduction ( E 1/2 = 0.925 V) evolution j 10 1.54 reactions, surpassing those Pt/C‐RuO 2 catalysts. calculations reveal that electronic interaction nitrogen‐doped matrix plays a critical role in boosting performance. Additionally, rechargeable Zn‐Air battery (ZAB) assembled aqueous electrolyte exhibits largest power density 371.6 mW cm −2 outstanding cycling durability (over 2000 h). Furthermore, all‐solid‐state cable‐type ZAB delivers high flexibility good stability energy efficiency (76.5%). This work will open avenue adjust metal‐carbon support for functional electrocatalysis hierarchical porous structure design.

Language: Английский

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CoIn dual-atom catalyst for hydrogen peroxide production via oxygen reduction reaction in acid

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Aug. 8, 2023

The two-electron oxygen reduction reaction in acid is highly attractive to produce H2O2, a commodity chemical vital various industry and household scenarios, which still hindered by the sluggish kinetics. Herein, both density function theory calculation in-situ characterization demonstrate that dual-atom CoIn catalyst, O-affinitive In atom triggers favorable stable adsorption of hydroxyl, effectively optimizes OOH on neighboring Co. As result, Co atoms shifts pathway for efficient H2O2 production acid. partial current reaches 1.92 mA cm-2 at 0.65 V rotating ring-disk electrode test, while rate as high 9.68 mol g-1 h-1 three-phase flow cell. Additionally, CoIn-N-C presents excellent stability during long-term operation, verifying practicability catalyst. This work provides inspiring insights into rational design active catalysts other catalytic systems.

Language: Английский

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Pt Single Atom Electrocatalysts at Graphene Edges for Efficient Alkaline Hydrogen Evolution

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 32(38)

Published: July 10, 2022

Abstract Graphene edges exhibit a highly localized density of states that result in increased reactivity compared to its basal plane. However, exploiting this anchor and tune the electronic single atom catalysts (SACs) remains elusive. To investigate this, method Pt SACs with ultra‐low mass loadings at edge‐rich vertically aligned graphene (as low as 0.71 µg cm –2 ) is developed. Angle‐dependent X‐ray absorption spectroscopy density‐functional theory calculations reveal edge‐anchored has robust coupling π‐electrons graphene. This interaction results higher occupancy 5d orbital, shifting d ‐band center toward Fermi level, improving adsorption *H for hydrogen evolution reaction (HER). primarily coordinated edge shows improved alkaline HER performance mixed environments (turnover frequencies 22.6 10.9 s –1 an overpotential 150 mV, respectively). work demonstrates effective route engineering coordination environment by using enhanced energy conversion reactions.

Language: Английский

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Atomically Dispersed Co–S–N Active Sites Anchored on Hierarchically Porous Carbon for Efficient Catalytic Hydrogenation of Nitro Compounds

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(10), P. 5786 - 5794

Published: April 29, 2022

It is highly desired but challenging to develop non-noble metal-based hydrogenation catalysts that can replace noble ones for selective reduction of nitro compounds into amino compounds. Herein, we reported a hierarchically porous carbon-supported N,S dual-coordinated cobalt single-atom catalyst (Co1/NSC-AT) The unique coordination environment Co centers, combined with the structure carbon supports, endows Co1/NSC-AT an excellent catalytic performance; reaction be efficiently performed under mild conditions (35 °C, ∼1bar H2) high conversion and selectivity. theoretical calculation reveals center (Co1S1N3) in acts as active site reaction. Co1S1N3 possesses lower barrier rate-determining step than Co1N4 nanoparticles. Moreover, environments tailor electronic structures single atoms, which facilitate desorption H from sites, thus promoting process.

Language: Английский

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Single‐atomic Co‐B ₂ N ₂ sites anchored on carbon nanotube arrays promote lithium polysulfide conversion in lithium–sulfur batteries

Carbon Energy, Journal Year: 2023, Volume and Issue: 5(11)

Published: March 23, 2023

Abstract Due to low cost, high capacity, and energy density, lithium–sulfur (Li–S) batteries have attracted much attention; however, their cycling performance was largely limited by the poor redox kinetics sulfur utilization. Herein, predicted density functional theory calculations, single‐atomic Co‐B 2 N site‐imbedded boron nitrogen co‐doped carbon nanotubes (SA‐Co/BNC) were designed accomplish loading, fast kinetic, long service period Li–S batteries. Experiments proved that atomic sites can effectively catalyze lithium polysulfide conversion. Therefore, electrodes delivered a specific capacity of 1106 mAh g −1 at 0.2 C after 100 cycles exhibited an outstanding cycle over 1000 1 with decay rate 0.032% per cycle. Our study offers new strategy couple combined effect nanocarriers catalysts in novel coordination environments for high‐performance

Language: Английский

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Understanding Synergistic Catalysis on Cu‐Se Dual Atom Sites viaOperandoX‐ray Absorption Spectroscopy in Oxygen Reduction Reaction

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(13)

Published: Jan. 24, 2023

The construction and understanding of synergy in well-defined dual-atom active sites is an available avenue to promote multistep tandem catalytic reactions. Herein, we construct a dual-hetero-atom catalyst that comprises adjacent Cu-N4 Se-C3 for efficient oxygen reduction reaction (ORR) activity. Operando X-ray absorption spectroscopy coupled with theoretical calculations provide in-depth insights into this mechanism ORR under realistic device operation conditions. heteroatom Se modulator can efficiently polarize the charge distribution around symmetrical moieties, serve as synergistic site facilitate second step simultaneously, which key OOH*-(Cu1 -N4 ) transforms O*-(Se1 -C2 intermediate on sites. Therefore, designed achieves satisfied alkaline activity half-wave potential 0.905 V vs. RHE maximum power density 206.5 mW cm-2 Zn-air battery.

Language: Английский

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