Unveiling the Activity Origin of a Copper‐based Electrocatalyst for Selective Nitrate Reduction to Ammonia

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(13), P. 5350 - 5354

Published: Jan. 22, 2020

Abstract Unveiling the active phase of catalytic materials under reaction conditions is important for construction efficient electrocatalysts selective nitrate reduction to ammonia. The origin prominent activity enhancement CuO (Faradaic efficiency: 95.8 %, Selectivity: 81.2 %) toward electroreduction ammonia was probed. 15 N isotope labeling experiments showed that originated from reduction. 1 H NMR spectroscopy and colorimetric methods were performed quantify In situ Raman ex revealed electrochemically converted into Cu/Cu 2 O, which serves as an phase. combined results online differential electrochemical mass spectrometry (DEMS) DFT calculations demonstrated electron transfer Cu O at interface could facilitate formation *NOH intermediate suppress hydrogen evolution reaction, leading high selectivity Faradaic efficiency.

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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Recent Advances on Water‐Splitting Electrocatalysis Mediated by Noble‐Metal‐Based Nanostructured Materials

Advanced Energy Materials, Journal Year: 2020, Volume and Issue: 10(11)

Published: Feb. 6, 2020

Abstract Electrochemical water splitting plays a crucial role in the development of clean and renewable energy production conversion, which is promising pathway to reduce social dependence on fossil fuels. Thus, highly active, cost‐efficient, robust catalysts must be developed reaction overpotential increase electrocatalytic efficiency. In this review, recent research efforts toward developing advanced electrocatalysts based noble metals with outstanding performance for catalysis, mainly dependent their structure engineering, are summarized. First, simple description water‐splitting mechanism some engineering strategies given, including heteroatom incorporation, strain interface/hybrid single atomic construction. Then, underlying relationship between metal electronic/geometric discussed assistance theoretical simulation. Finally, personal perspective provided order highlight challenges opportunities novel suitable wide range commercial uses structural applications.

Language: Английский

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Advanced Electrocatalysts with Single-Metal-Atom Active Sites

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(21), P. 12217 - 12314

Published: Nov. 2, 2020

Electrocatalysts with single metal atoms as active sites have received increasing attention owing to their high atomic utilization efficiency and exotic catalytic activity selectivity. This review aims provide a comprehensive summary on the recent development of such single-atom electrocatalysts (SAECs) for various energy-conversion reactions. The discussion starts an introduction different types SAECs, followed by overview synthetic methodologies control dispersion atomically resolved characterization using state-of-the-art microscopic spectroscopic techniques. In recognition extensive applications electrocatalytic studies are dissected in terms important electrochemical reactions, including hydrogen evolution reaction (HER), oxygen (OER), reduction (ORR), carbon dioxide (CO2RR), nitrogen (NRR). Examples SAECs deliberated each case performance, structure-property relationships, enhancement mechanisms. A perspective is provided at end section about remaining challenges opportunities targeted reaction.

Language: Английский

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Single-Atom Catalysts Based on the Metal–Oxide Interaction

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(21), P. 11986 - 12043

Published: Oct. 28, 2020

Metal atoms dispersed on the oxide supports constitute a large category of single-atom catalysts. In this review, supported catalysts are discussed about their synthetic procedures, characterizations, and reaction mechanism in thermocatalysis, such as water-gas shift reaction, selective oxidation/hydrogenation, coupling reactions. Some typical materials, including ferric oxide, cerium titanium dioxide, aluminum so on, intentionally mentioned for unique roles anchoring metal taking part catalytic The interactions between summarized to give picture how stabilize atomic centers, rationally tune geometric structures electronic states single atoms. Furthermore, several directions fabricating with improved performance proposed basis state-of-the-art understanding metal-oxide interactions.

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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Recent Advances and Prospective in Ruthenium-Based Materials for Electrochemical Water Splitting

ACS Catalysis, Journal Year: 2019, Volume and Issue: 9(11), P. 9973 - 10011

Published: Sept. 25, 2019

As a highly appealing technology for hydrogen generation, water electrolysis including oxygen evolution reaction (OER) at the anode and (HER) cathode largely depends on availability of efficient electrocatalysts. Accordingly, over past years, much effort has been made to develop various electrocatalysts with superior performance reduced cost. Among them, ruthenium (Ru)-based materials OER HER are very promising because their prominent catalytic activity, pH-universal application, cheapest price among precious metal family, so on. Herein, recent advances in this hot research field comprehensively reviewed. A general description about splitting is presented understand mechanism proposed scaling relations toward activities, key stability issues Ru-based further given. Subsequently, Ru-involving introduced classified into different groups improving or optimizing electrocatalytic properties, special focus several significant bifunctional along simulated electrolyzer. Finally, perspective existing challenges future progress catalysts provided. The main aim here shed some light design construction emerging energy storage conversion technologies.

Language: Английский

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Engineering single-atomic ruthenium catalytic sites on defective nickel-iron layered double hydroxide for overall water splitting

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: July 28, 2021

Abstract Rational design of single atom catalyst is critical for efficient sustainable energy conversion. However, the atomic-level control active sites essential electrocatalytic materials in alkaline electrolyte. Moreover, well-defined surface structures lead to in-depth understanding catalytic mechanisms. Herein, we report a single-atomic-site ruthenium stabilized on defective nickel-iron layered double hydroxide nanosheets (Ru 1 /D-NiFe LDH). Under precise regulation local coordination environments catalytically and existence defects, Ru LDH delivers an ultralow overpotential 18 mV at 10 mA cm −2 hydrogen evolution reaction, surpassing commercial Pt/C catalyst. Density functional theory calculations reveal that optimizes adsorption energies intermediates reaction promotes O–O coupling Ru–O site oxygen reaction. The as ideal model reveals superior water splitting performance with potential development promising water-alkali electrocatalysts.

Language: Английский

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Dynamic oxygen adsorption on single-atomic Ruthenium catalyst with high performance for acidic oxygen evolution reaction

Nature Communications, Journal Year: 2019, Volume and Issue: 10(1)

Published: Oct. 24, 2019

Abstract Achieving active and stable oxygen evolution reaction (OER) in acid media based on single-atom catalysts is highly promising for cost-effective sustainable energy supply proton electrolyte membrane electrolyzers. Here, we report an atomically dispersed Ru 1 -N 4 site anchored nitrogen-carbon support (Ru-N-C) as efficient durable electrocatalyst acidic OER. The Ru-N-C catalyst delivers exceptionally intrinsic activity, reaching a mass activity high 3571 A g metal −1 turnover frequency of 3348 O 2 h with low overpotential 267 mV at current density 10 mA cm −2 . shows no evident deactivation or decomposition after 30-hour operation environment. Operando synchrotron radiation X-ray absorption spectroscopy infrared identify the dynamic adsorption single atom under working potentials, theoretical calculations demonstrate that O-Ru responsible OER stability.

Language: Английский

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Missing-linker metal-organic frameworks for oxygen evolution reaction

Nature Communications, Journal Year: 2019, Volume and Issue: 10(1)

Published: Nov. 6, 2019

Abstract Metal-organic frameworks (MOFs) have been recognized as compelling platforms for the development of miscellaneous applications because their structural diversity and functional tunability. Here, we propose that electrocatalytic properties could be well modified by incorporating missing linkers into MOF. Theoretical calculations suggest electronic structure MOFs can tuned introducing linkers, which improves oxygen evolution reaction (OER) performance Inspired these aspects, introduced various a layered-pillared MOF Co 2 (OH) (C 8 H 4 O ) (termed CoBDC) to prepare missing-linker MOFs. Transmission electron microscope synchrotron X-ray measurements confirmed in controlled our strategy. The self-supported nanoarrays with carboxyferrocene exhibit excellent OER ultralow overpotential 241 mV at 100 mA cm −2 . This work opens new prospect develop efficient MOF-based electrocatalysts linkers.

Language: Английский

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