Single-Atom Catalysts across the Periodic Table

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(21), P. 11703 - 11809

Published: Oct. 21, 2020

Isolated atoms featuring unique reactivity are at the heart of enzymatic and homogeneous catalysts. In contrast, although concept has long existed, single-atom heterogeneous catalysts (SACs) have only recently gained prominence. Host materials similar functions to ligands in catalysts, determining stability, local environment, electronic properties isolated thus providing a platform for tailoring targeted applications. Within just decade, we witnessed many examples SACs both disrupting diverse fields catalysis with their distinctive substantially enriching our understanding molecular processes on surfaces. To date, term SAC mostly refers late transition metal-based systems, but numerous exist which other elements play key catalytic roles. This review provides compositional encyclopedia SACs, celebrating 10th anniversary introduction this term. By defining broadest sense, explore full elemental diversity, joining different areas across whole periodic table, discussing historical milestones recent developments. particular, examine coordination structures associated accessed through distinct single-atom–host combinations relate them main applications thermo-, electro-, photocatalysis, revealing trends element-specific evolution, host design, uses. Finally, highlight frontiers field, including multimetallic atom proximity control, possible multistep cascade reactions, identifying challenges, propose directions future development flourishing field.

Language: Английский

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Regulating Fe-spin state by atomically dispersed Mn-N in Fe-N-C catalysts with high oxygen reduction activity

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: March 19, 2021

Abstract As low-cost electrocatalysts for oxygen reduction reaction applied to fuel cells and metal-air batteries, atomic-dispersed transition metal-nitrogen-carbon materials are emerging, but the genuine mechanism thereof is still arguable. Herein, by rational design synthesis of dual-metal atomically dispersed Fe,Mn/N-C catalyst as model object, we unravel that O 2 preferentially takes place on Fe III in FeN 4 /C system with intermediate spin state which possesses one e g electron (t 2g 4e 1) readily penetrating antibonding π-orbital oxygen. Both magnetic measurements theoretical calculation reveal adjacent Mn-N moieties can effectively activate sites both spin-state electronic modulation, rendering excellent ORR performances alkaline acidic media (halfwave positionals 0.928 V 0.1 M KOH, 0.804 HClO ), good durability, outperforms has almost same activity commercial Pt/C, respectively. In addition, it presents a superior power density 160.8 mW cm −2 long-term durability reversible zinc–air batteries. The work brings new insight into process active sites, undoubtedly leading exploration towards high effective non-precious catalysts.

Language: Английский

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Intrinsic Electrocatalytic Activity Regulation of M–N–C Single‐Atom Catalysts for the Oxygen Reduction Reaction

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(9), P. 4448 - 4463

Published: April 21, 2020

Abstract Single‐atom catalysts (SACs) with highly active sites atomically dispersed on substrates exhibit unique advantages regarding maximum atomic efficiency, abundant chemical structures, and extraordinary catalytic performances for multiple important reactions. In particular, M–N–C SACs (M=transition metal atom) demonstrate optimal electrocatalytic activity the oxygen reduction reaction (ORR) have attracted extensive attention recently. Despite substantial efforts in fabricating various SACs, principles regulating intrinsic of their not been sufficiently studied. this Review, we summarize regulation strategies promoting ORR by modulation center atoms, coordinated environmental guest groups. Theoretical calculations experimental investigations are both included to afford a comprehensive understanding structure–performance relationship. Finally, future directions developing advanced other analogous reactions proposed.

Language: Английский

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Recent advances of noble-metal-free bifunctional oxygen reduction and evolution electrocatalysts

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(13), P. 7745 - 7778

Published: Jan. 1, 2021

Bifunctional oxygen reduction and evolution constitute the core processes for sustainable energy storage. The advances on noble-metal-free bifunctional electrocatalysts are reviewed.

Language: Английский

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Theoretical Understandings of Graphene-based Metal Single-Atom Catalysts: Stability and Catalytic Performance

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(21), P. 12315 - 12341

Published: Oct. 28, 2020

Research on heterogeneous single-atom catalysts (SACs) has become an emerging frontier in catalysis science because of their advantages high utilization noble metals, precisely identified active sites, selectivity, and tunable activity. Graphene, as a one-atom-thick two-dimensional carbon material with unique structural electronic properties, been reported to be superb support for SACs. Herein, we provide overview recent progress investigations graphene-based Among the large number publications, will selectively focus stability metal single-atoms (SAs) anchored different sites graphene catalytic performances SACs chemical reactions, including thermocatalysis electrocatalysis. We summarize fundamental understandings structures intrinsic connection properties SACs, also brief perspective future design efficient graphene-like materials.

Language: Английский

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Engineering Dual Single‐Atom Sites on 2D Ultrathin N‐doped Carbon Nanosheets Attaining Ultra‐Low‐Temperature Zinc‐Air Battery

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(12)

Published: Jan. 7, 2022

Herein, a novel dual single-atom catalyst comprising adjacent Fe-N4 and Mn-N4 sites on 2D ultrathin N-doped carbon nanosheets with porous structure (FeMn-DSAC) was constructed as the cathode for flexible low-temperature Zn-air battery (ZAB). FeMn-DSAC exhibits remarkable bifunctional activities oxygen reduction reaction (ORR) evolution (OER). Control experiments density functional theory calculations reveal that catalytic activity arises from cooperative effect of Fe/Mn dual-sites aiding *OOH dissociation well nanosheet promoting active sits exposure mass transfer during process. The excellent enables ZAB to operate efficiently at ultra-low temperature -40 °C, delivering 30 mW cm-2 peak power retaining up 86 % specific capacity room counterpart.

Language: Английский

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Understanding the structure-performance relationship of active sites at atomic scale

Nano Research, Journal Year: 2022, Volume and Issue: 15(8), P. 6888 - 6923

Published: June 14, 2022

Language: Английский

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Simultaneously Achieving High Activity and Selectivity toward Two-Electron O₂ Electroreduction: The Power of Single-Atom Catalysts

ACS Catalysis, Journal Year: 2019, Volume and Issue: 9(12), P. 11042 - 11054

Published: Sept. 23, 2019

On-site production of hydrogen peroxide (H2O2) using electrochemical methods could be more efficient than the current industrial process. However, due to existence scaling relations for adsorption reaction intermediates, there is a long established trade-off between activity and selectivity catalysts, as enhancement catalytic typically accompanied by four-electron O2 reduction (ORR), leading reduced H2O2 production. Herein, means density functional theory (DFT) computations, we reported feasibility several classes important representative experimentally achievable single-atom catalysts (SACs) toward two-electron ORR, paying attention their stability, selectivity, at acidic medium. Starting from 210 two-dimensional (2D) SACs, demonstrated that 31 SACs have potential break metal-based simultaneously achieve high screened out 7 with higher PtHg4 in media. Especially, noble metal-free SAC, namely, single Zn atom centered phthalocyanine (Zn@Pc-N4), has remarkable improvement small overpotential 0.15 V. Moreover, multivariable analysis machine-learning techniques, provided comprehensive understanding underlying origin unveiled intrinsic correlations structure performance. This work may pave way design discovery promising materials

Language: Английский

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Coordination Engineering of Single‐Atom Catalysts for the Oxygen Reduction Reaction: A Review

Advanced Energy Materials, Journal Year: 2020, Volume and Issue: 11(3)

Published: Nov. 30, 2020

Abstract Future renewable energy supplies and a sustainable environment rely on many important catalytic processes. Single‐atom catalysts (SACs) are attractive because of their maximum atom utilization efficiency, tunable electronic structures, outstanding performance. Of particular note, transition‐metal SACs exhibit excellent activity selectivity for the oxygen reduction reaction (ORR)—an half in fuel cells metal–air batteries as well portable hydrogen peroxide (H 2 O ) production. Although considerable efforts have been made synthesis ORR, regulation coordination environments thus structures still pose big challenge. In this review, strategies manipulating classified into three categories, including center metal atoms, manipulation surrounding connecting to atom, modification geometric configuration support. Finally, some issues regarding future development ORR raised possible solutions proposed.

Language: Английский

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Molecular Design of Single‐Atom Catalysts for Oxygen Reduction Reaction

Advanced Energy Materials, Journal Year: 2020, Volume and Issue: 10(14)

Published: Feb. 25, 2020

Abstract Fuel cells are highly attractive for direct chemical‐to‐electrical energy conversion and represent the ultimate mobile power supply solution. However, presently, fuel limited by sluggish kinetics of cathodic oxygen reduction reaction (ORR), which requires use Pt as a catalyst, thus significantly increasing overall cost cells. Recently, nonprecious metal single‐atom catalysts (SACs) with high ORR activity under both acidic alkaline conditions have been recognized promising cost‐effective alternatives to replace in Considerable efforts devoted further improving SACs, including tailoring coordination structure centers, enriching concentration engineering electronic porosity substrate. Herein, brief introduction fundamentals parameters SACs origin their is provided, followed detailed review recently developed strategies used optimize rotating disk electrode membrane assembly tests. Remarks perspectives on remaining challenges future directions development commercial also presented.

Language: Английский

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