Heterogeneous Single-Atom Photocatalysts: Fundamentals and Applications

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(21), P. 12175 - 12216

Published: March 18, 2020

Single-atom photocatalysts have shown their compelling potential and arguably become the most active research direction in photocatalysis due to fascinating strengths enhancing light-harvesting, charge transfer dynamics, surface reactions of a photocatalytic system. While numerous comprehensions about single-atom recently been amassed, advanced characterization techniques vital theoretical studies are strengthening our understanding on these materials, allowing us forecast working mechanisms applications photocatalysis. In this review, we begin by describing general background definition photocatalysts. A brief discussion metal-support interactions is then provided. Thereafter, current available for summarized. After having some fundamental photocatalysts, advantages discussed. Finally, end review with look into remaining challenges future perspectives We anticipate that will provide inspiration discovery manifestly stimulating development emerging area.

Language: Английский

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Atomically precise alloy nanoclusters: syntheses, structures, and properties

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 49(17), P. 6443 - 6514

Published: Jan. 1, 2020

Atomically precise alloy nanoclusters have been continuously appealing to scientists owing their tunable electronic/geometric structures and enriched physicochemical properties.

Language: Английский

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Toward Active-Site Tailoring in Heterogeneous Catalysis by Atomically Precise Metal Nanoclusters with Crystallographic Structures

Chemical Reviews, Journal Year: 2020, Volume and Issue: 121(2), P. 567 - 648

Published: Sept. 17, 2020

Heterogeneous catalysis involves solid-state catalysts, among which metal nanoparticles occupy an important position. Unfortunately, no two from conventional synthesis are the same at atomic level, though such regular can be highly uniform nanometer level (e.g., size distribution ∼5%). In long pursuit of well-defined nanocatalysts, a recent success is atomically precise nanoclusters protected by ligands in range tens to hundreds atoms (equivalently 1–3 nm core diameter). More importantly, have been crystallographically characterized, just like protein structures enzyme catalysis. Such merge features homogeneous catalysts ligand-protected centers) and enzymes protein-encapsulated clusters few bridged ligands). The with their total available constitute new class model hold great promise fundamental research, including dependent activity, control catalytic selectivity structure surface ligands, structure–property relationships atomic-level, insights into molecular activation mechanisms, identification active sites on nanocatalysts. This Review summarizes progress utilization for These nanocluster-based enabled heterogeneous research single-atom single-electron levels. Future efforts expected achieve more exciting understanding tailoring design high activity under mild conditions.

Language: Английский

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Role of the Support in Gold-Containing Nanoparticles as Heterogeneous Catalysts

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(8), P. 3890 - 3938

Published: March 30, 2020

In this review, we discuss selected examples from recent literature on the role of support directing nanostructures Au-based monometallic and bimetallic nanoparticles. The is then discussed in relation to catalytic properties nanoparticles using different gas phase liquid reactions. reactions include CO oxidation, aerobic oxidation monohydric polyhydric alcohols, selective hydrogenation alkynes, nitroaromatics, CO2 hydrogenation, C-C coupling, methane oxidation. Only studies where has been explicitly studied detail have for discussion. However, also examined involving unsupported metal (i.e., colloidal nanoparticles). It clear that functionality can play a crucial tuning activity observed advanced theory characterization add greatly our understanding these fascinating catalysts.

Language: Английский

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Supported Metal Clusters: Fabrication and Application in Heterogeneous Catalysis

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(19), P. 11011 - 11045

Published: Aug. 31, 2020

Different from isolated metal atoms and large nanoparticles (NPs), supported clusters (SMCs) possess distinct geometric electronic structures thus exhibit enhanced activity designated selectivity in catalysis. So far, with the development synthetic methodologies characterization techniques, SMCs fine could be constructed well-defined at atomic level. In addition, based on computational modeling of SMCs, theoretical calculations corroborated well experimental results, providing in-depth insights into structure–property relationship for this Review, classic strategies key techniques are summarized. Subsequently, applications important catalytic reactions recent studies discussed, including aerobic oxidation, hydrogenation, dehydrogenation, water–gas shift (WGS) reaction, photocatalytic reactions. particular, importance cluster size-effect metal–support interactions determining performance is highlighted. Lastly, challenges prospects SMCs' catalysis illustrated.

Language: Английский

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An Adjacent Atomic Platinum Site Enables Single‐Atom Iron with High Oxygen Reduction Reaction Performance

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(35), P. 19262 - 19271

Published: June 22, 2021

Abstract The modulation effect has been widely investigated to tune the electronic state of single‐atomic M‐N‐C catalysts enhance activity oxygen reduction reaction (ORR). However, in‐depth study is rarely reported for isolated dual‐atomic metal sites. Now, catalytic activities Fe‐N 4 moiety can be enhanced by adjacent Pt‐N through effect, in which acts as modulator 3d orbitals active site and optimize ORR activity. Inspired this principle, we design synthesize electrocatalyst that comprises /Pt‐N moieties dispersed nitrogen‐doped carbon matrix (Fe‐N @NC) exhibits a half‐wave potential 0.93 V vs. RHE negligible degradation (ΔE 1/2 =8 mV) after 10000 cycles 0.1 M KOH. We also demonstrate not effective optimizing performances Co‐N Mn‐N systems.

Language: Английский

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Electrochemical oxidation of biomass derived 5-hydroxymethylfurfural (HMF): pathway, mechanism, catalysts and coupling reactions

Green Chemistry, Journal Year: 2021, Volume and Issue: 23(12), P. 4228 - 4254

Published: Jan. 1, 2021

HMF electrooxidation is emerging as a powerful and promising method to produce wide range of high-value chemicals on account mild operation conditions, controllable selectivity, scalability.

Language: Английский

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Computational Methods in Heterogeneous Catalysis

Chemical Reviews, Journal Year: 2020, Volume and Issue: 121(2), P. 1007 - 1048

Published: Dec. 22, 2020

The unprecedented ability of computations to probe atomic-level details catalytic systems holds immense promise for the fundamentals-based bottom-up design novel heterogeneous catalysts, which are at heart chemical and energy sectors industry. Here, we critically analyze recent advances in computational catalysis. First, will survey progress electronic structure methods atomistic catalyst models employed, have enabled catalysis community build increasingly intricate, realistic, accurate active sites supported transition-metal catalysts. We then review developments microkinetic modeling, specifically mean-field kinetic Monte Carlo simulations, bridge gap between nanoscale insights macroscale experimental kinetics data with increasing fidelity. finally advancements theoretical accelerating discovery. Throughout review, provide ample examples applications, discuss remaining challenges, our outlook near future.

Language: Английский

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Cyclic (Alkyl)- and (Aryl)-(amino)carbene Coinage Metal Complexes and Their Applications

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(9), P. 4141 - 4168

Published: April 2, 2020

Cyclic (alkyl)- and (aryl)-(amino)carbenes (CAACs CAArCs) are stronger σ-donors π-acceptors than imidazol-2-ylidenes imidazolidin-2-ylidenes, the well-known N-heterocyclic carbenes (NHCs). Consequently, they form strong bonds with coinage metals stabilize both low high oxidation states. This Review shows that CAACs CAArCs have allowed for isolation of copper gold complexes were believed to be only transient intermediates. has not a better understanding mechanism known processes but also led development novel metal-catalyzed reactions. In addition their role in homogeneous catalysis, CAAC CAArC metal recently found applications medicinal chemistry, as well materials science. When possible, performance ligands compared those classical NHCs.

Language: Английский

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Determination of the Evolution of Heterogeneous Single Metal Atoms and Nanoclusters under Reaction Conditions: Which Are the Working Catalytic Sites?

ACS Catalysis, Journal Year: 2019, Volume and Issue: 9(12), P. 10626 - 10639

Published: Oct. 25, 2019

Identification of active sites in heterogeneous metal catalysts is critical for understanding the reaction mechanism at molecular level and designing more efficient catalysts. Because their structural flexibility, subnanometric catalysts, including single atoms clusters with a few atoms, can exhibit dynamic evolution when interacting substrate molecules, making it difficult to determine catalytically sites. In this work, Pt containing selected types entities (from nanoparticles) have been prepared, has followed, while they were reacting variety catalytic reactions, selective hydrogenation CO oxidation, dehydrogenation propane, photocatalytic H2 reaction. By situ X-ray absorption spectroscopy, IR high-resolution electron microscopy techniques, we will show that some characterization techniques carried out an inadequate way introduce confusion on interpretation coordination environment highly dispersed species. Finally, combination reactivity shows that, depending catalyst–reactant interaction metal–support interaction, singly rapidly evolve into or nanoparticles, being working those abovementioned reactions.

Language: Английский

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