Efficient Capture and Electroreduction of Dilute CO₂ into Highly Pure and Concentrated Formic Acid Aqueous Solution

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(20), P. 14349 - 14356

Published: May 14, 2024

High-purity CO2 rather than dilute (15 vol %, CO2/N2/O2 = 15:80:5, v/v/v) similar to the flue gas is currently used as feedstock for electroreduction of CO2, and liquid products are usually mixed up with cathode electrolyte, resulting in high product separation costs. In this work, we showed that a microporous conductive Bi-based metal–organic framework (Bi-HHTP, HHTP 2,3,6,7,10,11-hexahydroxytriphenylene) can not only efficiently capture from under humidity but also catalyze adsorbed into formic acid current density 80 mA cm–2 Faradaic efficiency 90% at very low cell voltage 2.6 V. Importantly, performance atmosphere was close high-purity atmosphere. This first catalyst maintain exceptional eCO2RR presence both O2 N2. Moreover, by using feedstock, 1 working electrode coating Bi-HHTP continuously produce 200 mM aqueous solution relative purity 100% least 30 h membrane assembly (MEA) electrolyzer. The does contain electrolytes, such highly concentrated pure be directly an electrolyte fuel cells. Comprehensive studies revealed might ascribed ability micropores on lower Gibbs free energy formation key intermediate *OCHO open Bi sites.

Language: Английский

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Engineering Copper‐Based Covalent Organic Framework Microenvironments to Enable Efficient CO₂ Electroreduction with Tunable Ethylene/Methane Switch

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(24)

Published: Feb. 5, 2024

Abstract A microenvironment engineering strategy has been developed to switch the CO 2 electroreduction reaction (CO RR) selectivity from methane (CH 4 ) ethylene (C H by adjusting coordination microstructures of trinuclear copper cluster‐based metal‐covalent organic framework (MCOF). When Cu sites are oriented channels in Cu‐PyCA‐MCOF, is main product. Conversely, when coordinated with OH − and O molecules Cu‐PyCAOH‐MCOF nanosheets, product switches CH C 50.5% 200.2 mA cm partial current density at −1.2 V (vs RHE). This happens because can only contact active perpendicular cluster plane where Cu─Cu distance between them 3.2 Å, favoring efficient conversion through C─C coupling reaction. Operando infrared spectroscopy, situ X‐ray absorption near‐edge structure spectra, DFT calculations reveal that changing environments MCOFs significantly stabilizes key intermediates reduces energies RR. work offers an effective for enhancing RR performance toward products tuning microenvironments copper‐based electrocatalysts.

Language: Английский

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MOF-Based Electrocatalysts: An Overview from the Perspective of Structural Design

Chemical Reviews, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 18, 2025

The electrocatalytic technique, as an efficient energy storage and conversion technology, has attracted significant attention to address exhaustion environmental pollution. Usually, the activity selectivity of reactions are largely dominated by dynamic process occurring on electrocatalysts. Therefore, high-performance electrocatalysts, which can dominate pathway barrier reactions, great significance for advancement technique. Metal-organic frameworks (MOFs), emerging crystalline porous materials, present structural component advantages including well-defined structure, high surface area, large porosity, diverse components, easy tailorability, demonstrating fantastic potential precise fabrication In this Review, strategies in electrocatalysts based MOF-related materials specifically introduced from aspects catalytic site design microenvironment modulation around sites. Furthermore, representative progress achieved various applications employing MOF-based is systematically summarized, with special emphasis MOFs performance optimization. Finally, remaining challenges future perspectives further highlighted.

Language: Английский

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Modulated Multicomponent Reaction Pathway by Pore‐Confinement Effect in MOFs for Highly Efficient Catalysis of Low‐Concentration CO₂

Angewandte Chemie International Edition, Journal Year: 2025, Volume and Issue: unknown

Published: March 11, 2025

Abstract The conversion of flue gas CO 2 into high‐value chemicals via multicomponent reactions (MCRs) offers the advantages atom economy, bond‐formation efficiency and product complexity. However, because competition between reaction sequences pathways among substrates, efficient synthesize desired is a great challenge. Herein, porous noble‐metal‐free framework ( Cu‐TCA) was synthesized, which can highly effectively catalyze by modulating pathways. pores with size 6.5 Å×6.5 Å in Cu‐TCA selectively permit entry propargylamine at simulated concentrations, At same time, larger‐sized phosphine oxide hindered outside pores. Control experiments NMR spectroscopy revealed that preferentially reacted to form oxazolidinones, further produce phosphorylated 2‐oxazolidinones. Therefore, sequence substrates were controlled confinement effect . Density functional theory (DFT) calculations supported coordination alkyne, significantly reducing barrier promoting catalytic reaction. This study developed new strategy for regulating promote MCRs MOF.

Language: Английский

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Tandem Acidic CO₂ Electrolysis Coupled with Syngas Fermentation: A Two-Stage Process for Producing Medium-Chain Fatty Acids

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(17), P. 7445 - 7456

Published: April 15, 2024

The tandem application of CO2 electrolysis with syngas fermentation holds promise for achieving heightened production rates and improved product quality. However, the significant impact composition on mixed culture-based microbial chain elongation remains unclear. Additionally, effective methods generating an adjustable from acidic are currently lacking. This study successfully demonstrated medium-chain fatty acids through fermentation. CO could serve as sole energy source or electron donor (when cofed acetate) caproate generation. Furthermore, results gas diffusion electrode structure engineering highlighted that use carbon black, either alone in combination graphite, enabled consistent generation (pH 1). black layer significantly selectivity, increasing 0% to 43.5% (0.05 M K+) further 92.4% (0.5 K+). enhancement performance was attributed promotion K+ accumulation, stabilizing catalytically active sites, rather than creating a localized alkaline environment CO2-to-CO conversion. research contributes advancement hybrid technology sustainable reduction chemical production.

Language: Английский

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Recent strategies to improve the electroactivity of metal–organic frameworks for advanced electrocatalysis

Deleted Journal, Journal Year: 2024, Volume and Issue: 1(2), P. 181 - 206

Published: Aug. 4, 2024

Abstract Metal–organic frameworks (MOFs) have emerged as promising materials in the realm of electrocatalysis due to their high surface area, tunable porosity, and versatile chemical functionality. However, practical application has been hampered by inherent limitations such low electrical conductivity a limited number active metal sites. Researchers addressed these challenges through various strategies, including enhancing incorporating conductive nanoparticles, modifying structure composition MOFs replacing nodes functionalizing linkers, preparing catalysts thermal processes decarburization conversion into oxides, phosphides (MPs), sulfides (MSs). This review provided comprehensive summary strategies that were employed enhance electroactivity for improved electrocatalytic performance recent years. It also explored future directions potential innovations design synthesis MOF‐based electrocatalysts, offering valuable insights advancing sustainable energy technologies.

Language: Английский

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Molecular Enhancement of Direct Electrolysis of Dilute CO₂

ACS Energy Letters, Journal Year: 2024, Volume and Issue: 9(3), P. 911 - 918

Published: Feb. 9, 2024

Producing chemicals and fuels via direct electrolysis of dilute CO2 derived from industrial point sources can improve the economic feasibility technology, yet it suffers many challenges owing to unfavorable mass transport, reaction thermodynamics, kinetics. Here we report a molecular enhancement strategy for stream with 10% concentration in typical flue gas, using commercially available cobalt phthalocyanine (CoPc) catalyst. A poly(4-vinylpyridine) (P4VP)-modified CoPc electrode exhibits remarkable CO partial current density 252 mA cm–2 Faradaic efficiency 90% under feed, 2.24-fold higher than that bare electrode. The integration molecule P4VP modifier abundant pyridine moieties creates microenvironment sequentially capturing activating CO2, thus resulting impressive electrocatalytic performance. presented paves way utilization gas.

Language: Английский

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Constructing Co₄(SO₄)₄ Clusters within Metal–Organic Frameworks for Efficient Oxygen Electrocatalysis

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(38)

Published: Aug. 3, 2024

Abstract Multinuclear metal clusters are ideal candidates to catalyze small molecule activation reactions involving the transfer of multiple electrons. However, synthesizing active is a big challenge. Herein, on constructing an unparalleled Co 4 (SO ) cluster within porphyrin‐based metal–organic frameworks (MOFs) and electrocatalytic features such for oxygen evolution reaction (OER) reduction (ORR) reported. The II sulfate complexes tetrakis(4‐pyridyl)porphyrin under solvothermal conditions afforded ‐M‐MOFs (M═Co, Cu, Zn). Crystallographic studies revealed that these have same framework structure, having connected by metalloporphyrin units through Co─N pyridyl bonds. In cluster, four ions chemically symmetrically equivalent each coordinated with O atoms give distorted cube‐like structure. Electrocatalytic showed all OER ORR. Importantly, regulating activity units, it confirmed electrocatalysis. With use porphyrins as connecting ‐Co‐MOF displays highest in this series MOFs showing 10 mA cm −2 current density at 357 mV overpotential ORR half‐wave potential 0.83 V versus reversible hydrogen electrode (RHE). Theoretical synergistic effect two proximal facilitating formation O─O This work fundamental significance present construction structures electrocatalysis demonstrate cooperation between during bond process.

Language: Английский

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Modulating the Electronic Properties of Single Ni Atom Catalyst via First‐Shell Coordination Engineering to Boost Electrocatalytic Flue Gas CO₂ Reduction

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 10, 2025

Abstract Electrochemical converting CO 2 to via single atom catalyst is an effective strategy for reducing concentration in the atmosphere and achieving a carbon‐neutral cycle. However, relatively low industrial processes large energy barriers activating severely obstruct actual application. Reasonably modulating coordination shell of active center enhance activity catalysts. Herein, well‐designed single‐atom electrocatalyst Ni‐N 3 S 1 developed large‐scale synthesis strategy. The constructed S‐C exhibits superior catalytic than 4 ‐C conversion H‐type cells, industrial‐level current density with excellent durability at wide pH range can be achieved gas‐diffusion flow cells. Experimental results functional theory (DFT) calculation demonstrate that introducing electronegative significantly regulate electronic structure site, promoting adsorption capacity decreasing barrier *COOH formation, thus larger size flexibility sulfur mitigate nickel agglomeration stability catalyst. This work provides designing highly catalysts electrocatalysis reactive sites.

Language: Английский

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Sub‐Nanometer Mono‐Layered Metal–Organic Frameworks Nanosheets for Simulated Flue Gas Photoreduction

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(27)

Published: April 18, 2024

Abstract The dilemma between the thickness and accessible active site triggers design of porous crystalline materials with mono‐layered structure for advanced photo‐catalysis applications. Here, a kind sub‐nanometer nanosheets (Co‐MOF MNSs) through exfoliation specifically designed Co 3 cluster‐based metal–organic frameworks (MOFs) is reported. inherent light‐sensitivity endow Co‐MOF MNSs fully exposed Janus sites that can selectively photo‐reduce CO 2 into formic acid under simulated flue gas. Notably, production efficiency by (0.85 mmol g −1 h ) ≈13 times higher than bulk counterpart (0.065 gas atmosphere, which highest in reported works up to date. Theoretical calculations prove simultaneously available possess activity when compared single site, validating importance nanosheet morphology. These results may facilitate development functional photo‐reduction potential treatment.

Language: Английский

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