Stabilizing Cu²⁺ Ions by Solid Solutions to Promote CO₂ Electroreduction to Methane

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(5), P. 2079 - 2084

Published: Jan. 28, 2022

Copper is the only metal catalyst that can perform electrocatalytic CO2 reduction reaction (CRR) to produce hydrocarbons and oxygenates. Its surface oxidation state determines pathway various products. However, under cathodic potential of CRR conditions, chemical composition most Cu-based catalysts inevitably undergoes electroreduction from Cu2+ Cu0 or Cu1+ species, which generally coupled with phase reconstruction formation new active sites. Since initial sites are hard retain, there have been few studies about for CRR. Herein we propose a solid-solution strategy stabilize ions by incorporating them into CeO2 matrix, works as self-sacrificing ingredient protect species. In situ spectroscopic characterization density functional theory calculations reveal compared conventionally derived Cu sites, species in solid solution (Cu-Ce-Ox) significantly strengthen adsorption *CO intermediate, facilitating its further hydrogenation CH4 instead dimerization give C2 As result, different other catalysts, Cu-Ce-Ox delivered high Faradaic efficiency 67.8% low value 3.6% C2H4.

Language: Английский

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Thermo-, Electro-, and Photocatalytic CO₂ Conversion to Value-Added Products over Porous Metal/Covalent Organic Frameworks

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(20), P. 2978 - 2997

Published: Sept. 26, 2022

ConspectusThe continuing increase of the concentration atmospheric CO2 has caused many environmental issues including climate change. Catalytic conversion using thermochemical, electrochemical, and photochemical methods is a potential technique to decrease simultaneously obtain value-added chemicals. Due high energy barrier however, this method still far from large-scale applications which requires activity, selectivity, stability. Therefore, development efficient catalysts convert different products urgent. With their well-engineered pores chemical compositions, surface area, elevated adsorption capability, adjustable active sites, porous crystalline frameworks metal-organic (MOFs) covalent organic (COFs) are materials for catalytic conversion. Here, we summarize our recent work on MOFs COFs thermocatalytic, electrocatalytic, photocatalytic describe structure-activity relationships that could guide design effective catalysts.The first section paper describes imidazolium-functionalized MOFs, liquid cationic with nucleophilic halogen ions, can promote thermocatalytically cycloaddition reaction epoxides toward cyclic carbonates at one bar pressure. A MOF takes role reservoir tackle low local concentrations in gas-liquid-solid heterogeneous reactions. Imidazolium-functionalized ions avoid use cocatalysts, leads milder more facile experimental conditions separation processes.In dealing electrocatalytic reduction (CO2RR), developed series conductive framework fast electron transmission capabilities, afford current densities outperform traditional COF have been reported. The intrinsically two-dimensional 2D nanosheets based fully π-conjugated phthalocyanine motif excellent transport capability were prepared, strong transporters also integrated into metalloporphyrin-based CO2RR. Cu2O quantum dots Cu nanoparticles (NPs) be uniformly dispersed MOFs/COFs synergistic and/or tandem electrocatalysts, achieve highly selective production CH4 or C2H4 CO2RR.A third efforts facilitate electron-hole photocatalysis. Our focus regulation coordination spheres fabrication architecture heterojunctions, engineering films reduction.Finally, discuss several problems associated studies consider some prospects

Language: Английский

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Two-Dimensional Conjugated Metal–Organic Frameworks for Electrocatalysis: Opportunities and Challenges

ACS Nano, Journal Year: 2022, Volume and Issue: 16(2), P. 1759 - 1780

Published: Jan. 20, 2022

A highly effective electrocatalyst is the central component of advanced electrochemical energy conversion. Recently, two-dimensional conjugated metal-organic frameworks (2D c-MOFs) have emerged as a class promising electrocatalysts because their advantages including 2D layered structure with high in-plane conjugation, intrinsic electrical conductivity, permanent pores, large surface area, chemical stability, and structural diversity. In this Review, we summarize recent advances c-MOF for First, introduce design principles synthetic strategies reported c-MOFs, well functional electrocatalysis. Subsequently, present representative in various reactions, such hydrogen/oxygen evolution, reduction reactions oxygen, carbon dioxide, nitrogen. We highlight property tuning to boost catalytic performance, offer our perspectives regard challenges be overcome.

Language: Английский

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A rational design of functional porous frameworks for electrocatalytic CO₂reduction reaction

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(4), P. 1382 - 1427

Published: Jan. 1, 2023

Rational design of functional porous frameworks for electrocatalytic CO 2 reduction reaction.

Language: Английский

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Mesoporous Polyimide‐Linked Covalent Organic Framework with Multiple Redox‐Active Sites for High‐Performance Cathodic Li Storage

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(31)

Published: May 31, 2022

Covalent organic frameworks (COFs) are gaining increasing attention as renewable cathode materials for Li-ion batteries. However, COF electrodes reported so far still exhibit unsatisfying capacity due to their limited active site density and insufficient utilization. Herein, a new two-dimensional polyimide-linked COF, HATN-AQ-COF with multiple redox-active sites storing Li+ ions, was designed fabricated from module of 2,3,8,9,14,15-hexacarboxyl hexaazatrinaphthalene trianhydrides 2,6-diaminoanthraquinone linker. possessing excellent stability, good conductivity, large pore size 3.8 nm enables the stable fast ion transport. This, in combination abundant redox sites, results high reversible 319 mAh g-1 at 0.5 C (1 C=358 mA ) electrode utilization 89 % cycle performance, representing one best performances among electrodes.

Language: Английский

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The Crystal Plane is not the Key Factor for CO₂‐to‐Methane Electrosynthesis on Reconstructed Cu₂O Microparticles

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(7)

Published: Dec. 9, 2021

Cu2 O microparticles with controllable crystal planes and relatively high stability have been recognized as a good platform to understand the mechanism of electrocatalytic CO2 reduction reaction (CO2 RR). Herein, we demonstrate that in situ generated O/Cu interface plays key role determining selectivity methane formation, rather than initial plane reconstructed microparticles. Experimental results indicate evolution is dominated on all three different similar Tafel slopes long-term stabilities. Density functional theory (DFT) calculations further reveal *CO protonated via bridge configuration at interface, regardless O. The Gibbs free energy changes (ΔG) *CHO are close more negative *OCCOH, indicating formation favorable ethylene planes.

Language: Английский

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High‐Rate and Selective CO₂ Electrolysis to Ethylene via Metal–Organic‐Framework‐Augmented CO₂ Availability

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(51)

Published: Oct. 17, 2022

High-rate conversion of carbon dioxide (CO2 ) to ethylene (C2 H4 in the CO2 reduction reaction RR) requires fine control over phase boundary gas diffusion electrode (GDE) overcome limit solubility aqueous electrolytes. Here, a metal-organic framework (MOF)-functionalized GDE design is presented, based on catalysts:MOFs:hydrophobic substrate materials layered architecture, that leads high-rate and selective C2 production flow cells membrane assembly (MEA) electrolyzers. It found using electroanalysis operando X-ray absorption spectroscopy (XAS), MOF-induced organic layers GDEs augment local concentration near active sites Cu catalysts. MOFs with different adsorption abilities are used, stacking ordering varied. While sputtering poly(tetrafluoroethylene) (PTFE) (Cu/PTFE) exhibits 43% Faradaic efficiency (FE) at current density 200 mA cm-2 cell, 49% FE 1 A achieved MOF-augmented RR. further evaluated an MEA electrolyzer, achieving partial 220 for RR 121 monoxide (CORR), representing 2.7-fold 15-fold improvement rate, compared those obtained bare Cu/PTFE.

Language: Английский

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Tailoring Coordination Microenvironment of Cu(I) in Metal–Organic Frameworks for Enhancing Electroreduction of CO₂to CH₄

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 32(36)

Published: June 29, 2022

Abstract The coordination microenvironment of metal active sites in metal–organic frameworks (MOFs) plays a crucial role its performance for electrochemical CO 2 reduction reaction (CO RR). However, it remains challenge to clarify the structure–performance relationship RR catalyzed by MOFs. Herein, series MOFs with different microenvironments Cu(I) (CuCl, CuBr, and CuI) evaluate their performances is synthesized. With increasing radius halogen atom, adsorption capacity increases d‐band center Cu positively shifts Fermi level, leading enhance selectivity CH 4 conversion. CuI gives highest total Faradaic efficiency (FE) 83.2%, FE up 57.2% partial current density 60.7 mA cm −2 at −1.08 V versus reversible hydrogen electrode. Theoretical calculations reveal that shifted site contributes reduced formation energies *CH O 3 intermediates, which potential‐determining step thus facilitates electrocatalytic . This study opens new avenue studying between electroreduction

Language: Английский

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Strategies for enhancing the catalytic activity and electronic conductivity of MOFs-based electrocatalysts

Coordination Chemistry Reviews, Journal Year: 2022, Volume and Issue: 478, P. 214969 - 214969

Published: Dec. 14, 2022

Language: Английский

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Flexible Cuprous Triazolate Frameworks as Highly Stable and Efficient Electrocatalysts for CO₂ Reduction with Tunable C₂H₄/CH₄ Selectivity

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(28)

Published: May 5, 2022

Cu-based metal-organic frameworks have attracted much attention for electrocatalytic CO2 reduction, but they are generally instable and difficult to control the product selectivity. We report flexible Cu(I) triazolate as efficient, stable, tunable electrocatalysts reduction C2 H4 /CH4 . By changing size of ligand side groups, selectivity ratio can be gradually tuned inversed from 11.8 : 1 2.6, giving , CH4 hydrocarbon selectivities up 51 %, 56 77 respectively. After long-term electrocatalysis, retain structures/morphologies without formation inorganic species. Computational simulations showed that coordination geometry changed triangular tetrahedral bind reaction intermediates, two adjacent cooperated C-C coupling form Importantly, groups controlled catalyst flexibility by steric hindrance mechanism, pathway is more sensitive than one.

Language: Английский

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