Tailoring Acidic Oxygen Reduction Selectivity on Single-Atom Catalysts via Modification of First and Second Coordination Spheres

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(20), P. 7819 - 7827

Published: May 13, 2021

Product selectivity in multielectron electrocatalytic reactions is crucial to energy conversion efficiency and chemical production. However, a present practical drawback the limited understanding of actual catalytic active sites. Here, using as prototype single-atom catalysts (SACs) acidic oxygen reduction reaction (ORR), we report structure–property relationship show for first time that molecular-level local structure, including second coordination spheres (CSs), rather than individual atoms, synergistically determines response. ORR on Co-SACs can be tailored from four-electron two-electron pathway by modifying (N or/and O coordination) (C–O–C groups) CSs. Using combined theoretical predictions experiments, X-ray absorption fine structure analyses situ infrared spectroscopy, confirm unique change originates structure-dependent shift sites center Co atom O-adjacent C atom. We this optimizes electronic *OOH adsorption behavior give "best" activity >95% H2O2 electrosynthesis.

Language: Английский

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Electrocatalytic Refinery for Sustainable Production of Fuels and Chemicals

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(36), P. 19572 - 19590

Published: Feb. 19, 2021

Abstract Compared to modern fossil‐fuel‐based refineries, the emerging electrocatalytic refinery (e‐refinery) is a more sustainable and environmentally benign strategy convert renewable feedstocks energy sources into transportable fuels value‐added chemicals. A crucial step in conducting e‐refinery processes development of appropriate reactions optimal electrocatalysts for efficient cleavage formation chemical bonds. However, compared well‐studied primary (e.g., O 2 reduction, water splitting), mechanistic aspects materials design complex are yet be settled. To address this challenge, herein, we first present fundamentals heterogeneous electrocatalysis some reactions, then implement these establish framework by coupling situ generated intermediates (integrated reactions) or products (tandem reactions). We also set principles strategies efficiently manipulate reaction pathways.

Language: Английский

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Metal–Organic Frameworks Derived Functional Materials for Electrochemical Energy Storage and Conversion: A Mini Review

Nano Letters, Journal Year: 2021, Volume and Issue: 21(4), P. 1555 - 1565

Published: Feb. 11, 2021

With many apparent advantages including high surface area, tunable pore sizes and topologies, diverse periodic organic–inorganic ingredients, metal–organic frameworks (MOFs) have been identified as versatile precursors or sacrificial templates for preparing functional materials advanced electrodes high-efficiency catalysts electrochemical energy storage conversion (EESC). In this Mini Review, we first briefly summarize the material design strategies to show rich possibilities of chemical compositions physical structures MOFs derivatives. We next highlight latest advances focusing on composition/structure/performance relationship discuss their practical applications in various EESC systems, such supercapacitors, rechargeable batteries, fuel cells, water electrolyzers, carbon dioxide/nitrogen reduction reactions. Finally, provide some our own insights into major challenges prospective solutions MOF-derived EESC, hoping shed light future development highly exciting field.

Language: Английский

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Unraveling the electronegativity-dominated intermediate adsorption on high-entropy alloy electrocatalysts

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

Published: May 13, 2022

Abstract High-entropy alloys have received considerable attention in the field of catalysis due to their exceptional properties. However, few studies hitherto focus on origin outstanding performance and accurate identification active centers. Herein, we report a conceptual experimental approach overcome limitations single-element catalysts by designing FeCoNiXRu (X: Cu, Cr, Mn) system with various sites that different adsorption capacities for multiple intermediates. The electronegativity differences between mixed elements HEA induce significant charge redistribution create highly Co Ru optimized energy barriers simultaneously stabilizing OH * H intermediates, which greatly enhances efficiency water dissociation alkaline conditions. This work provides an in-depth understanding interactions specific opens up fascinating direction breaking scaling relation issues multistep reactions.

Language: Английский

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Emerging Dual‐Atomic‐Site Catalysts for Efficient Energy Catalysis

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(36)

Published: July 23, 2021

Atomically dispersed metal catalysts with well-defined structures have been the research hotspot in heterogeneous catalysis because of their high atomic utilization efficiency, outstanding activity, and selectivity. Dual-atomic-site (DASCs), as an extension single-atom (SACs), recently drawn surging attention. The DASCs possess higher loading, more sophisticated flexible active sites, offering chance for achieving better catalytic performance, compared SACs. In this review, recent advances on how to design new enhancing energy will be highlighted. It start classification marriage two kinds homonuclear heteronuclear according configuration sites. Then, state-of-the-art characterization techniques discussed. Different synthetic methods applications various reactions, including oxygen reduction reaction, carbon dioxide monoxide oxidation others followed. Finally, major challenges perspectives provided.

Language: Английский

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The Progress and Outlook of Metal Single-Atom-Site Catalysis

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(40), P. 18155 - 18174

Published: Sept. 29, 2022

Single-atom-site catalysts (SASCs) featuring maximized atom utilization and isolated active sites have progressed tremendously in recent years as a highly prosperous branch of catalysis research. Varieties SASCs been developed that show excellent performance many catalytic applications. The major goal SASC research is to establish feasible synthetic strategies for the preparation high-performance catalysts, achieve an in-depth understanding active-site structures mechanisms, develop practical with industrial value. This Perspective describes up-to-date development related such dual-atom-site (DASCs) nano-single-atom-site (NSASCs), analyzes current challenges encountered by these applications, proposes their possible future path.

Language: Английский

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Atomically Dispersed Fe–Co Dual Metal Sites as Bifunctional Oxygen Electrocatalysts for Rechargeable and Flexible Zn–Air Batteries

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(2), P. 1216 - 1227

Published: Jan. 5, 2022

Single-metal site catalysts have exhibited highly efficient electrocatalytic properties due to their unique coordination environments and adjustable local structures for reactant adsorption electron transfer. They been widely studied many electrochemical reactions, including oxygen reduction reaction (ORR) evolution (OER). However, it remains a significant challenge realize high-efficiency bifunctional catalysis (ORR/OER) with single-metal-type active sites. Herein, we report atomically dispersed Fe–Co dual metal sites (FeCo–NC) derived from Fe Co co-doped zeolitic imidazolate frameworks (ZIF-8s), aiming build up multiple ORR/OER catalysts. The FeCo–NC catalyst shows excellent catalytic activity in alkaline media the ORR (E1/2 = 0.877 V) OER (Ej=10 1.579 V). Moreover, its outstanding stability during is comparable noble-metal (Pt/C RuO2). atomic dispersion state, structure, charge density difference of were characterized determined using advanced physical characterization functional theory (DFT) calculations. FeCo–N6 moieties are likely main simultaneously improved performance relative traditional single We further incorporated into an air electrode fabricating rechargeable flexible Zn–air batteries, generating superior power (372 mW cm–2) long-cycle (over 190 h) stability. This work would provide method design synthesize multi-metal electrocatalysis.

Language: Английский

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Descriptors for the Evaluation of Electrocatalytic Reactions: d‐Band Theory and Beyond

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 32(4)

Published: Oct. 13, 2021

Abstract Closing the carbon‐, hydrogen‐, and nitrogen cycle with renewable electricity holds promises for mitigation of facing environment energy crisis, along continuing prosperity human society. Descriptors bridge gap between physicochemical factors electrocatalysts their boosted activity serve as guiding principles during rational design electrocatalysts. The optimal adsorption strength key intermediates is potentially accessed under tendentious guidelines proposed by indicators, such d‐band center, Δ G H , E O* coordination number (CN), bond length, etc. Here, in this review, a comprehensive summary recent advances achieved regarding descriptors that aims recycling C/H/N‐containing chemicals offered. review initiated providing necessity development efficient then physics behind center introduced. Then progress relating to guidance reviewed. Following that, an extended discussion experimental or theoretical characterization beyond it provided. Finally, perspectives challenges area are

Language: Английский

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Clusters Induced Electron Redistribution to Tune Oxygen Reduction Activity of Transition Metal Single‐Atom for Metal–Air Batteries

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(12)

Published: Dec. 27, 2021

Oxygen reduction reaction (ORR) activity can be effectively tuned by modulating the electron configuration and optimizing chemical bonds. Herein, a general strategy to optimize of metal single-atoms is achieved decoration clusters via coating-pyrolysis-etching route. In this unique structure, are able induce redistribution modulate M-N species bond lengths. As result, M-ACSA@NC exhibits superior ORR compared with nanoparticle-decorated counterparts. The performance enhancement attributed optimized intermediates desorption benefiting from electronic configuration. Theoretical analysis reinforces significant roles correlating cluster-induced charge transfer. proof-of-concept, various metal-air batteries assembled Fe-ACSA@NC deliver remarkable power densities capacities. This an effective universal technique for modulation M-N-C, which shows great potential in application energy storage devices.

Language: Английский

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Confining and Highly Dispersing Single Polyoxometalate Clusters in Covalent Organic Frameworks by Covalent Linkages for CO₂ Photoreduction

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(4), P. 1861 - 1871

Published: Jan. 20, 2022

Single clusters have attracted extensive research interest in the field of catalysis. However, achieving a highly uniform dispersion single-cluster catalyst is challenging. In this work, for first time, we present versatile strategy uniformly dispersed polyoxometalates (POMs) covalent organic frameworks (COFs) through confining POM cluster into regular nanopores COF by linkage. These COF-POM composites combine properties light absorption, electron transfer, and suitable catalytic active sites; as result, they exhibit outstanding activity artificial photosynthesis: that is, CO2 photoreduction with H2O donor. Among them, TCOF-MnMo6 achieved highest CO yield (37.25 μmol g-1 h-1 ca. 100% selectivity) gas-solid reaction system. Furthermore, mechanism study based on density functional theory (DFT) calculations demonstrated photoinduced transfer (PET) process occurs from to POM, then reduction oxidation occur COF, respectively. This work developed method single which also shows potential using materials photocatalysis.

Language: Английский

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