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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Superiority of Dual‐Atom Catalysts in Electrocatalysis: One Step Further Than Single‐Atom Catalysts

Advanced Energy Materials, Journal Year: 2022, Volume and Issue: 12(9)

Published: Jan. 18, 2022

Abstract In recent years, dual‐atom catalysts (DACs) have attracted extensive attention, as an extension of single‐atom (SACs). Compared with SACs, DACs higher metal loading and more complex flexible active sites, thus achieving better catalytic performance providing opportunities for electrocatalysis. This review introduces the research progress in years on how to design new enhance Firstly, advantages increasing are introduced. Then, role changing adsorption condition reactant molecules atoms is discussed. Moreover, ways which can reduce reaction energy barrier key steps change path explored. Catalytic applications different electrocatalytic reactions, including carbon dioxide reduction reaction, oxygen evolution hydrogen nitrogen followed. Finally, a brief summary made challenges prospects

Language: Английский

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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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Fe/Cu diatomic catalysts for electrochemical nitrate reduction to ammonia

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

Published: June 19, 2023

Electrochemical conversion of nitrate to ammonia offers an efficient approach reducing pollutants and a potential technology for low-temperature low-pressure synthesis. However, the process is limited by multiple competing reactions NO3- adsorption on cathode surfaces. Here, we report Fe/Cu diatomic catalyst holey nitrogen-doped graphene which exhibits high catalytic activities selectivity production. The enables maximum Faradaic efficiency 92.51% (-0.3 V(RHE)) NH3 yield rate 1.08 mmol h-1 mg-1 (at - 0.5 V(RHE)). Computational theoretical analysis reveals that relatively strong interaction between promotes discharge anions. Nitrogen-oxygen bonds are also shown be weakened due existence hetero-atomic dual sites lowers overall reaction barriers. dual-site hetero-atom strategy in this work provides flexible design further development expands electrocatalytic techniques reduction

Language: Английский

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Emerging low-nuclearity supported metal catalysts with atomic level precision for efficient heterogeneous catalysis

Nano Research, Journal Year: 2022, Volume and Issue: 15(9), P. 7806 - 7839

Published: June 2, 2022

Language: Английский

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A durable half-metallic diatomic catalyst for efficient oxygen reduction

Energy & Environmental Science, Journal Year: 2022, Volume and Issue: 15(4), P. 1601 - 1610

Published: Jan. 1, 2022

By elaborately constructing a Fe–Zn based diatomic catalyst, the active center is changed from FeN 4– ZnN 4 to Zn–N 2 after protonation, leading well-maintained structure and thus high stability of ORR.

Language: Английский

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Synergy of Pd atoms and oxygen vacancies on In2O3 for methane conversion under visible light

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: May 25, 2022

Methane (CH4) oxidation to high value chemicals under mild conditions through photocatalysis is a sustainable and appealing pathway, nevertheless confronting the critical issues regarding both conversion selectivity. Herein, visible irradiation (420 nm), synergy of palladium (Pd) atom cocatalyst oxygen vacancies (OVs) on In2O3 nanorods enables superior photocatalytic CH4 activation by O2. The optimized catalyst reaches ca. 100 μmol h-1 C1 oxygenates, with selectivity primary products (CH3OH CH3OOH) up 82.5%. Mechanism investigation elucidates that such induced dedicated function Pd single atoms boosting hole electron transfer, respectively. O2 proven be only source for CH3OH production, while H2O acts as promoter efficient ·OH production facilitates product desorption indicated DFT modeling. This work thus provides new understandings simultaneous regulation activity cocatalysts vacancies.

Language: Английский

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Precisely Constructing Orbital Coupling-Modulated Dual-Atom Fe Pair Sites for Synergistic CO₂ Electroreduction

ACS Energy Letters, Journal Year: 2022, Volume and Issue: 7(2), P. 640 - 649

Published: Jan. 14, 2022

Electrochemical reduction of CO2 (CO2RR) provides an attractive pathway to achieve a carbon-neutral energy cycle. Single-atom catalysts (SAC) have shown unique potential in heterogeneous catalysis, but their structural simplicity prevents them from breaking linear scaling relationships. In this study, we develop feasible strategy precisely construct series electrocatalysts featuring well-defined single-atom and dual-site iron anchored on nitrogen-doped carbon matrix (Fe1–N–C Fe2–N–C). The Fe2–N–C dual-atom electrocatalyst (DAC) achieves enhanced CO Faradaic efficiency above 80% wider applied ranges along with higher turnover frequency (26,637 h–1) better durability compared SAC counterparts. Furthermore, based in-depth experimental theoretical analysis, the orbital coupling between dual sites decreases gap antibonding bonding states *CO adsorption. This research presents new insights into structure–performance relationship CO2RR at atomic scale extends application DACs for electrocatalysis beyond.

Language: Английский

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Carbon Nitride Photocatalysts with Integrated Oxidation and Reduction Atomic Active Centers for Improved CO₂Conversion

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(34)

Published: June 18, 2022

Single-atom active-site catalysts have attracted significant attention in the field of photocatalytic CO2 conversion. However, designing active sites for reduction and H2 O oxidation simultaneously on a photocatalyst combining corresponding half-reaction system is still difficult. Here, we synthesized bimetallic single-atom with two compatible centers Mn Co carbon nitride (Mn1 Co1 /CN). Our experimental results density functional theory calculations showed that center promotes by accumulating photogenerated holes. In addition, activation increasing bond length angle molecules. Benefiting from synergistic effect atomic centers, Mn1 /CN exhibited CO production rate 47 μmol g-1 h-1 , which significantly higher than single-metal photocatalyst.

Language: Английский

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Isolating Single and Few Atoms for Enhanced Catalysis

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(39)

Published: May 17, 2022

Abstract Atomically dispersed metal catalysts have triggered great interest in the field of catalysis owing to their unique features. Isolated single or few atoms can be anchored on substrates via chemical bonding space confinement maximize atom utilization efficiency. The key challenge lies precisely regulating geometric and electronic structure active centers, thus significantly influencing catalytic properties. Although several reviews been published preparation, characterization, application single‐atom (SACs), comprehensive understanding SACs, dual‐atom (DACs), atomic clusters has never systematically summarized. Here, recent advances engineering local environments state‐of‐the‐art DACs, for enhanced performance are highlighted. Firstly, various synthesis approaches presented. Then, special attention is focused elucidation terms state coordination structure. Furthermore, a summary isolated applications thermocatalysis, electrocatalysis, photocatalysis provided. Finally, potential challenges future opportunities this emerging This review will pave way regulate microenvironment site boosting processes.

Language: Английский

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