Oxygen Evolution/Reduction Reaction Catalysts: From In Situ Monitoring and Reaction Mechanisms to Rational Design

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(9), P. 6257 - 6358

Published: March 21, 2023

The oxygen evolution reaction (OER) and reduction (ORR) are core steps of various energy conversion storage systems. However, their sluggish kinetics, i.e., the demanding multielectron transfer processes, still render OER/ORR catalysts less efficient for practical applications. Moreover, complexity catalyst–electrolyte interface makes a comprehensive understanding intrinsic mechanisms challenging. Fortunately, recent advances in situ/operando characterization techniques have facilitated kinetic monitoring under conditions. Here we provide selected highlights mechanistic studies with main emphasis placed on heterogeneous systems (primarily discussing first-row transition metals which operate basic conditions), followed by brief outlook molecular catalysts. Key sections this review focused determination true active species, identification sites, reactive intermediates. For in-depth insights into above factors, short overview metrics accurate characterizations is provided. A combination obtained time-resolved information reliable activity data will then guide rational design new Strategies such as optimizing restructuring process well overcoming adsorption-energy scaling relations be discussed. Finally, pending current challenges prospects toward development homogeneous presented.

Language: Английский

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Engineering the Electronic Structure of Single‐Atom Iron Sites with Boosted Oxygen Bifunctional Activity for Zinc–Air Batteries

Advanced Materials, Journal Year: 2022, Volume and Issue: 35(9)

Published: Dec. 19, 2022

Abstract Rechargeable zinc–air batteries typically require efficient, durable, and inexpensive bifunctional electrocatalysts to support oxygen reduction/evolution reactions (ORR/OER). However, sluggish kinetics mass transportation challenges must be addressed if the performance of these catalysts is enhanced. Herein, a strategy fabricate catalyst comprising atomically dispersed iron atoms supported on mesoporous nitrogen‐doped carbon (Fe SAs/NC) with accessible metal sites optimized electronic metal–support interactions developed. Both experimental results theoretical calculations reveal that engineered structures active can regulate charge distribution Fe centers optimize adsorption/desorption oxygenated intermediates. The SAs/NC containing 1 N 4 O achieves remarkable ORR activity over entire pH range, half‐wave potentials 0.93, 0.83, 0.75 V (vs reversible hydrogen electrode) in alkaline, acidic, neutral electrolytes, respectively. In addition, it demonstrates promising low overpotential 320 mV at 10 mA cm −2 for OER alkaline conditions. battery assembled exhibits superior than Pt/C+RuO 2 counterpart terms peak power density, specific capacity, cycling stability. These findings demonstrate importance structure engineering directing catalytic activity.

Language: Английский

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Geometric and Electronic Engineering of Atomically Dispersed Copper‐Cobalt Diatomic Sites for Synergistic Promotion of Bifunctional Oxygen Electrocatalysis in Zinc–Air Batteries

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(25)

Published: April 11, 2023

The development of rechargeable zinc-air batteries is heavily dependent on bifunctional oxygen electrocatalysts to offer exceptional reduction/evolution reaction (ORR/OER) activities. However, the design such with high activity and durability challenging. Herein, a strategy proposed create an electrocatalyst comprised copper-cobalt diatomic sites highly porous nitrogen-doped carbon matrix (Cu-Co/NC) abundantly accessible metal optimal geometric electronic structures. Experimental findings theoretical calculations demonstrate that synergistic effect Cu-Co dual-metal metal-N4 coordination induce asymmetric charge distributions moderate adsorption/desorption behavior intermediates. This exhibits extraordinary electrocatalytic activities in alkaline media, half-wave potential 0.92 V for ORR low overpotential 335 mV at 10 mA cm-2 OER. In addition, it demonstrates acidic (0.85 V) neutral (0.74 media. When applied battery, achieves operational performance outstanding (510 h), ranking as one most efficient reported date. work importance engineering isolated boosting electrochemical energy devices.

Language: Английский

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Single‐Atom Catalysis in Organic Synthesis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(34)

Published: March 15, 2023

Single-atom catalysts hold the potential to significantly impact chemical sector, pushing boundaries of catalysis in new, uncharted directions. These materials, featuring isolated metal species ligated on solid supports, can exist many coordination environments, all which have shown important functions specific transformations. Their emergence has also provided exciting opportunities for mimicking metalloenzymes and bridging gap between homogeneous heterogeneous catalysis. This Review outlines impressive progress made recent years regarding use single-atom organic synthesis. We illustrate knowledge gaps search more sustainable, earth-abundant synthetic applications.

Language: Английский

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Modulating adsorbed hydrogen drives electrochemical CO2-to-C2 products

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

Published: Aug. 1, 2023

Electrocatalytic CO2 reduction is a typical reaction involving two reactants (CO2 and H2O). However, the role of H2O dissociation, which provides active *H species to multiple protonation steps, usually overlooked. Herein, we construct dual-active sites catalyst comprising atomic Cu nanoparticles supported on N-doped carbon matrix. Efficient electrosynthesis multi-carbon products achieved with Faradaic efficiency approaching 75.4% partial current density 289.2 mA cm-2 at -0.6 V. Experimental theoretical studies reveal that facilitate C-C coupling step through *CHO dimerization, while boost dissociation form *H. The generated migrate modulate coverage NPs, thus promote *CO-to-*CHO. effect single-sites gives rise catalytic performance.

Language: Английский

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Cu-based high-entropy two-dimensional oxide as stable and active photothermal catalyst

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

Published: June 1, 2023

Cu-based nanocatalysts are the cornerstone of various industrial catalytic processes. Synergistically strengthening stability and activity is an ongoing challenge. Herein, high-entropy principle applied to modify structure nanocatalysts, a PVP templated method invented for generally synthesizing six-eleven dissimilar elements as two-dimensional (2D) materials. Taking 2D Cu2Zn1Al0.5Ce5Zr0.5Ox example, not only enhances sintering resistance from 400 °C 800 but also improves its CO2 hydrogenation pure CO production rate 417.2 mmol g-1 h-1 at 500 °C, 4 times higher than that reported advanced catalysts. When photothermal hydrogenation, it exhibits record photochemical energy conversion efficiency 36.2%, with generation 248.5 571 L yield under ambient sunlight irradiation. The materials provide new route simultaneously achieve activity, greatly expanding application boundaries catalysis.

Language: Английский

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Structural Regulation of Covalent Organic Frameworks for Catalysis

Accounts of Chemical Research, Journal Year: 2024, Volume and Issue: 57(8), P. 1214 - 1226

Published: March 29, 2024

ConspectusChemical reactions can be promoted at lower temperatures and pressures, thereby reducing the energy input, by introducing suitable catalysts. Despite its significance, quest for efficient stable catalysts remains a significant challenge. In this context, addressing efficiency of stands out as paramount concern. However, challenges posed vague structure limited tailorability traditional would make it highly desirable to fabricate optimized based on understanding structure–activity relationships. Covalent organic frameworks (COFs), subclass fully designed crystalline materials formed polymerization building blocks through covalent bonds have garnered widespread attention in catalysis. The precise customizable structures COFs, coupled with attributes such high surface area facile functional modification, COFs attractive molecular platforms catalytic applications. These inherent advantages position ideal catalysts, facilitating elucidation structure-performance relationships further improving Nevertheless, there is lack systematic emphasis summary structural regulation atomic/molecular level COF Consequently, growing need summarize research field provide deep insights into COF-based catalysis promote development.In Account, we will recent advances achieved placing an design enhanced Considering unique components present fundamental principles rational This Account starts presenting overview explaining why are promising Then, introduce principle Next, following three aspects specific strategies catalysts: (1) By designing different groups integrating metal species unit, activity and/or selectivity finely modulated. (2) Regulating linkage facilitates charge transfer modulates electronic sites, accordingly, intrinsic activity/selectivity improved. (3) means pore wall/space engineering, microenvironment surrounding sites modulated optimize performance. Finally, current future developments discussed detail. provides insight toward their performance, which inspiration other heterogeneous

Language: Английский

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Catalysts driving efficiency and innovation in thermal reactions: A comprehensive review

Green Technologies and Sustainability, Journal Year: 2024, Volume and Issue: 2(2), P. 100078 - 100078

Published: Feb. 17, 2024

Language: Английский

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Solvent-free selective hydrogenation of nitroaromatics to azoxy compounds over Co single atoms decorated on Nb2O5 nanomeshes

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

Published: April 12, 2024

Abstract The solvent-free selective hydrogenation of nitroaromatics to azoxy compounds is highly important, yet challenging. Herein, we report an efficient strategy construct individually dispersed Co atoms decorated on niobium pentaoxide nanomeshes with unique geometric and electronic properties. use this supported single atom catalysts in the nitrobenzene azoxybenzene results high catalytic activity selectivity, 99% selectivity conversion within 0.5 h. Remarkably, it delivers exceptionally turnover frequency 40377 h –1 , which amongst similar state-of-the-art catalysts. In addition, demonstrates remarkable recyclability, reaction scalability, wide substrate scope. Density functional theory calculations reveal that are significantly promoted by properties strong metal-support interaction 1 /Nb 2 O 5 . absence precious metals, toxic solvents, reagents makes catalyst more appealing for synthesizing from nitroaromatics. Our findings suggest great potential access boosted thus offering blueprints design nanomaterials organocatalysis.

Language: Английский

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Fabricating a Structured Single‐Atom Catalyst via High‐Resolution Photopolymerization 3D Printing

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: April 29, 2024

Abstract This study introduces a novel solution to the design of structured catalysts, integrating single‐piece 3D printing with single‐atom catalysis. Structured catalysts are widely employed in industrial processes, as they provide optimal mass and heat transfer, leading more efficient use catalytic materials. They conventionally prepared using ceramic or metallic bodies, which then washcoated impregnated catalytically active layers. However, this approach may lead adhesion issues latter. By employing photopolymerization printing, stable catalyst is directly shaped into stand‐alone, material. The battery characterization methods present confirms uniform distribution species structural integrity Computational fluid dynamics simulations applied demonstrate enhanced momentum transfer light within body. materials finally evaluated continuous‐flow photocatalytic oxidation benzyl alcohol benzaldehyde, relevant reaction prepare biomass‐derived building blocks. innovative reported herein manufacture circumvents complexities traditional synthetic methods, offering scalability efficiency improvements, highlights transformative role catalysis engineering revolutionize catalysts’ design.

Language: Английский

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