Chemical Synthesis of Single Atomic Site Catalysts

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(21), P. 11900 - 11955

Published: April 3, 2020

Manipulating metal atoms in a controllable way for the synthesis of materials with desired structure and properties is holy grail chemical synthesis. The recent emergence single atomic site catalysts (SASC) demonstrates that we are moving toward this goal. Owing to maximum efficiency atom-utilization unique structures properties, SASC have attracted extensive research attention interest. prerequisite scientific practical applications fabricate highly reactive stable on appropriate supports. In review, various synthetic strategies summarized concrete examples highlighting key issues methods stabilize supports suppress their migration agglomeration. Next, discuss how conditions affect catalytic before ending review by prospects challenges as well further researches SASC.

Language: Английский

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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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Metal–Organic Framework-Based Catalysts with Single Metal Sites

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(21), P. 12089 - 12174

Published: May 1, 2020

Metal-organic frameworks (MOFs) are a class of distinctive porous crystalline materials constructed by metal ions/clusters and organic linkers. Owing to their structural diversity, functional adjustability, high surface area, different types MOF-based single sites well exploited, including coordinately unsaturated from nodes metallolinkers, as active species immobilized MOFs. Furthermore, controllable thermal transformation MOFs can upgrade them nanomaterials functionalized with single-atom catalysts (SACs). These unique features derivatives enable serve highly versatile platform for catalysis, which has actually been becoming rapidly developing interdisciplinary research area. In this review, we overview the recent developments catalysis at in emphasis on structures applications thermocatalysis, electrocatalysis, photocatalysis. We also compare results summarize major insights gained works providing challenges prospects emerging field.

Language: Английский

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Atomic site electrocatalysts for water splitting, oxygen reduction and selective oxidation

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 49(7), P. 2215 - 2264

Published: Jan. 1, 2020

This review summarized the fabrication routes and characterization methods of atomic site electrocatalysts (ASCs) followed by their applications for water splitting, oxygen reduction selective oxidation.

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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Single‐Atom Catalysts for Electrocatalytic Applications

Advanced Functional Materials, Journal Year: 2020, Volume and Issue: 30(31)

Published: June 9, 2020

Abstract The recent advances in electrocatalysis for oxygen reduction reaction (ORR), evolution (OER), hydrogen (HER), oxidation (HOR), carbon dioxide (CO 2 RR), and nitrogen (NRR) are thoroughly reviewed. This comprehensive review focuses on the single‐atom catalysts (SACs) including Sc, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Sn, W, Bi, Ru, Rh, Pd, Ag, Ir, Pt, Au with single‐metal sites or dual‐metal sites. development of electrocatalysts novel configurations compositions is documented. understanding process–structure–property relationships highlighted. For SACs, their electrocatalytic performance stability fuel cells, zinc–air batteries, electrolyzers, CO RR, NRR summarized. challenges perspectives emerging field discussed.

Language: Английский

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Regulating the Coordination Environment of MOF‐Templated Single‐Atom Nickel Electrocatalysts for Boosting CO₂ Reduction

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(7), P. 2705 - 2709

Published: Dec. 10, 2019

The general synthesis and control of the coordination environment single-atom catalysts (SACs) remains a great challenge. Herein, host-guest cooperative protection strategy has been developed to construct SACs by introducing polypyrrole (PPy) into bimetallic metal-organic framework. As an example, introduction Mg2+ in MgNi-MOF-74 extends distance between adjacent Ni atoms; PPy guests serve as N source stabilize isolated atoms during pyrolysis. result, series (named NiSA -Nx -C) with different numbers have fabricated controlling pyrolysis temperature. Significantly, -N2 -C catalyst, lowest number, achieves high CO Faradaic efficiency (98 %) turnover frequency (1622 h-1 ), far superior those -N3 -N4 -C, electrocatalytic CO2 reduction. Theoretical calculations reveal that low number sites is favorable formation COOH* intermediate thus accounts for its activity.

Language: Английский

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3D N-doped ordered mesoporous carbon supported single-atom Fe-N-C catalysts with superior performance for oxygen reduction reaction and zinc-air battery

Applied Catalysis B Environment and Energy, Journal Year: 2020, Volume and Issue: 280, P. 119411 - 119411

Published: Aug. 11, 2020

Language: Английский

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Engineering Energy Level of Metal Center: Ru Single-Atom Site for Efficient and Durable Oxygen Reduction Catalysis

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(50), P. 19800 - 19806

Published: Nov. 25, 2019

Emerging as a new frontier in heterogeneous catalysis, single-atom site catalysts (SSCs) have sparked enormous attention and bring about opportunities to oxygen reduction electrocatalysis. Despite considerable progress achieved recently, most of the reported SSCs suffer from either insufficient activity or unsatisfactory stability, which severely retards their practical application. Here, we demonstrate novel Ru-SSC with appropriate adsorption free energy OH* (ΔGOH*) confer excellent low Fenton reactivity maintain long-term stability. The as-developed exhibits encouraging reaction turnover frequency 4.99 e– s–1 sites–1, far exceeding state-of-the-art Fe-SSC counterpart (0.816 sites–1), result Ru level regulation via spontaneous OH binding. Furthermore, greatly suppressed reactivity, restrained generation reactive species directly observed, thus endowing much more superior stability (only 17 mV negative shift after 20 000 cycles) than (31 mV). application is further validated by its real fuel cell device.

Language: Английский

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Electrocatalysis of Single-Atom Sites: Impacts of Atomic Coordination

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(14), P. 7584 - 7618

Published: June 11, 2020

Single metal atoms embedded within select supporting matrices have shown great potential in the development of high-efficiency, low-cost electrocatalysts because maximal atom utilization and mass activity. As single are stabilized by coordination bonds with substrate, strong metal–support interactions can be exploited for ready manipulation electrocatalytic activity selectivity toward target reactions. However, most single-atom catalysts (SACs) prepared pyrolysis contain a wide range structures. Resolving atomic configurations moieties represents critical first step establishment an unambiguous correlation between SAC structure In this Review, we summarize recent progress studies electrocatalysts, focus on impacts sites activities series reactions that important various electrochemical energy technologies, such as hydrogen evolution reaction, oxygen reduction nitrogen CO2 so on. The survey entails SACs, from noble metals (e.g., Pt, Pd, Ru, Ir, Au, etc.) to non-noble Fe, Co, Ni, Cu, etc.), supported variety substrate materials pristine doped carbon, metal, oxide, sulfide, etc.). Finally, Review concludes perspective highlighting promises challenges further SACs context chemistry.

Language: Английский

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