Bimetallic Sites for Catalysis: From Binuclear Metal Sites to Bimetallic Nanoclusters and Nanoparticles

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(8), P. 4855 - 4933

Published: March 27, 2023

Heterogeneous bimetallic catalysts have broad applications in industrial processes, but achieving a fundamental understanding on the nature of active sites at atomic and molecular level is very challenging due to structural complexity catalysts. Comparing features catalytic performances different entities will favor formation unified structure-reactivity relationships heterogeneous thereby facilitate upgrading current In this review, we discuss geometric electronic structures three representative types (bimetallic binuclear sites, nanoclusters, nanoparticles) then summarize synthesis methodologies characterization techniques for entities, with emphasis recent progress made past decade. The supported nanoparticles series important reactions are discussed. Finally, future research directions catalysis based and, more generally, prospective developments both practical applications.

Language: Английский

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Microenvironment Engineering of Single/Dual‐Atom Catalysts for Electrocatalytic Application

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(31)

Published: Feb. 23, 2023

Single/dual-metal atoms supported on carbon matrix can be modulated by coordination structure and neighboring active sites. Precisely designing the geometric electronic uncovering structure-property relationships of single/dual-metal confront with grand challenges. Herein, this review summarizes latest progress in microenvironment engineering single/dual-atom sites via a comprehensive comparison single-atom catalyst (SACs) dual-atom catalysts (DACs) term design principles, modulation strategy, theoretical understanding structure-performance correlations. Subsequently, recent advances several typical electrocatalysis process are discussed to get general reaction mechanisms finely-tuned SACs DACs. Finally, full-scaled summaries challenges prospects given for This will provide new inspiration development atomically dispersed electrocatalytic application.

Language: Английский

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Single Atom Catalysts for Selective Methane Oxidation to Oxygenates

ACS Nano, Journal Year: 2022, Volume and Issue: 16(6), P. 8557 - 8618

Published: May 31, 2022

Direct conversion of methane (CH4) to C1–2 liquid oxygenates is a captivating approach lock carbons in transportable value-added chemicals, while reducing global warming. Existing approaches utilizing the transformation CH4 fuel via tandemized steam reforming and Fischer–Tropsch synthesis are energy capital intensive. Chemocatalytic partial oxidation remains challenging due negligible electron affinity, poor C–H bond polarizability, high activation barrier. Transition-metal stoichiometric catalysts harsh oxidants reaction conditions perform poorly with randomized product distribution. Paradoxically, which active enough break also promote overoxidation, resulting CO2 generation reduced carbon balance. Developing can bonds selectively make useful chemicals at mild vital commercialization. Single atom (SACs) specifically coordinated metal centers on support have displayed intrigued reactivity selectivity for oxidation. SACs significantly reduce induced electrostatic polarization facilitate accelerated rate low temperature. The distinct metal–support interaction stabilize intermediate prevent overoxidation products. present review accounts recent progress field selective oxygenates. chemical nature catalytic sites, effects interaction, stabilization species minimize thoroughly discussed forward-looking perspective improve performance.

Language: Английский

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Dual-Atom Catalyst with N-Colligated Zn₁Co₁ Species as Dominant Active Sites for Propane Dehydrogenation

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 146(1), P. 263 - 273

Published: Dec. 18, 2023

Dual-atom catalysts (DACs) with paired active sites can provide unique intrinsic properties for heterogeneous catalysis, but the synergy of centers remains to be elucidated. Here, we develop a high-performance DAC Zn

Language: Английский

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Atomic Distance Engineering in Metal Catalysts to Regulate Catalytic Performance

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(3)

Published: Oct. 2, 2023

Abstract It is very important to understand the structure–performance relationship of metal catalysts by adjusting microstructure at atomic scale. The distance has an essential influence on composition environment active atom, which a key factor for design targeted with desired function. In this review, we discuss and summarize strategies changing from three aspects relate their effects reactivity catalysts. First, regulating bond length between coordination atom one single‐atom site catalytic performance are introduced. lengths affected strain effect support high‐shell doping can evolve during reaction. Next, sites discussed. Due space matching adsorption electron transport, be adjusted shortening distance. addition, arrangement spacing surface atoms nanocatalysts studied. Finally, comprehensive summary outlook given.

Language: Английский

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Direct Photocatalytic Synthesis of Acetic Acid from Methane and CO at Ambient Temperature Using Water as Oxidant

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(2), P. 1185 - 1193

Published: Jan. 2, 2023

Direct functionalization of methane selectively to value-added chemicals is still one the main challenges in modern science. Acetic acid an important industrial chemical produced nowadays by expensive and environmentally unfriendly carbonylation methanol using homogeneous catalysts. Here, we report a new photocatalytic reaction route synthesize acetic from CH4 CO at room temperature water as sole external oxygen source. The optimized photocatalyst consists TiO2 support ammonium phosphotungstic polyoxometalate (NPW) clusters anchored with isolated Pt single atoms (Pt1). It enables stable synthesis 5.7 mmol·L–1 solution 60 h selectivity over 90% 66% on liquid-phase carbon basis, respectively, production 99 mol per Pt. Combined isotopic situ spectroscopy investigation suggests that proceeds via oxidative Pt1 sites, activation facilitated water-derived hydroxyl radicals.

Language: Английский

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Retrofitting Zr-Oxo Nodes of UiO-66 by Ru Single Atoms to Boost Methane Hydroxylation with Nearly Total Selectivity

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(24), P. 13169 - 13180

Published: June 6, 2023

Direct selective oxidation of methane (DSOM) to high value-added oxygenates under mild conditions is attracting considerable interest. Although state-of-the-art supported metal catalysts can improve conversion, it still challenging avoid the deep oxygenates. Here, we develop a highly efficient metal-organic frameworks (MOFs)-supported single-atom Ru catalyst (Ru1/UiO-66) for DSOM reaction using H2O2 as an oxidant. It endows nearly 100% selectivity and excellent turnover frequency 185.4 h-1 production The yield order magnitude higher than that on UiO-66 alone several times nanoparticles or other conventional Ru1 catalysts, which show severe CO2 formation. Detailed characterizations density functional theory calculations reveal synergistic effect between electron-deficient site electron-rich Zr-oxo nodes Ru1/UiO-66. responsible activation CH4 via resulting Ru1═O* species, while undertake formation oxygenic radical species produce In particular, retrofitted by prune excess inactive O2 more •OH helping suppress over-oxidation

Language: Английский

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Maximizing Active Fe Species in ZSM-5 Zeolite Using Organic-Template-Free Synthesis for Efficient Selective Methane Oxidation

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(10), P. 5888 - 5898

Published: Feb. 14, 2023

The selective oxidation of CH4 in the aqueous phase to produce valuable chemicals has attracted considerable attention due its mild reaction conditions and simple process. As most widely studied catalyst for this reaction, Fe-ZSM-5 demonstrates high intrinsic activity selectivity; however, prepared using conventional methods a limited number active Fe sites, resulting low conversion per unit mass catalyst. This study reports facile organic-template-free synthesis strategy that enables incorporation more into zeolite framework with higher dispersion degree compared methods. Because incorporated way is readily transformed isolated extra-framework species under thermal treatment, overall effect method (Fe-HZ5-TF) 3 times as many catalytically sites Fe-ZSM-5. When used 0.5 M H2O2 at 75 °C, Fe-HZ5-TF produced C1 oxygenate yield 109.4 mmol gcat-1 h-1 (a HCOOH selectivity 91.1%), surpassing other catalysts reported date. Spectroscopic characterization density functional theory calculations revealed are mononuclear form [(H2O)3Fe(IV)═O]2+ bound Al pairs framework. differs from Fe-ZSM-5, where binuclear acts site. Analysis product evolution during suggests radical-driven pathway explain activation site subsequent oxygenates.

Language: Английский

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Regulating Au coverage for the direct oxidation of methane to methanol

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Jan. 17, 2024

Abstract The direct oxidation of methane to methanol under mild conditions is challenging owing its inadequate activity and low selectivity. A key objective improving the selective first carbon-hydrogen bond methane, while inhibiting remaining bonds ensure high yield selectivity methanol. Here we design ultrathin Pd x Au y nanosheets revealed a volcano-type relationship between binding strength hydroxyl radical on catalyst surface catalytic performance using experimental density functional theory results. Our investigations indicate trade-off reaction-triggering reaction-conversion steps in reaction process. optimized 3 1 exhibits production rate 147.8 millimoles per gram hour, with 98% at 70 °C, representing one most efficient catalysts for

Language: Английский

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Oxidative carbonylation of methane to acetic acid on an Fe-modified ZSM-5 zeolite

Applied Catalysis B Environment and Energy, Journal Year: 2023, Volume and Issue: 329, P. 122549 - 122549

Published: March 1, 2023

Language: Английский

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