Covalent organic frameworks towards photocatalytic applications: Design principles, achievements, and opportunities

Coordination Chemistry Reviews, Journal Year: 2022, Volume and Issue: 475, P. 214882 - 214882

Published: Oct. 14, 2022

Language: Английский

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Ultrafast electron transfer at the In2O3/Nb2O5 S-scheme interface for CO2 photoreduction

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: June 5, 2024

Abstract Constructing S-scheme heterojunctions proves proficient in achieving the spatial separation of potent photogenerated charge carriers for their participation photoreactions. Nonetheless, restricted contact areas between two phases within heterostructures lead to inefficient interfacial transport, resulting low photocatalytic efficiency from a kinetic perspective. Here, In 2 O 3 /Nb 5 are fabricated through straightforward one-step electrospinning technique, enabling intimate and thereby fostering ultrafast electron transfer (<10 ps), as analyzed via femtosecond transient absorption spectroscopy. As result, powerful photo-electrons holes accumulate Nb conduction band valence band, respectively, exhibiting extended long lifetimes facilitating involvement subsequent Combined with efficient chemisorption activation stable CO on , hybrid nanofibers demonstrate improved performance conversion.

Language: Английский

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A Stable and Conductive Covalent Organic Framework with Isolated Active Sites for Highly Selective Electroreduction of Carbon Dioxide to Acetate

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(36)

Published: June 13, 2022

Electroreduction of CO2 to acetate provides a promising strategy reduce emissions and store renewable energy, but is usually by-product. Here, we show stable conductive two-dimensional phthalocyanine-based covalent-organic framework (COF) as an electrocatalyst for reduction with single-product Faradaic efficiency (FE) 90.3(2)% at -0.8 V (vs. RHE) current density 12.5 mA cm-2 in 0.1 M KHCO3 solution. No obvious degradation was observed over 80 hours continuous operation. Combined the comparison properties other catalysts isolated metal active sites, theoretical calculations situ infrared spectroscopy revealed that copper-phthalocyanine site high electron conducive key step C-C coupling *CH3 produce acetate, can avoid *CO or *CHO ethylene ethanol.

Language: Английский

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Tuning the electronic structure of a metal–organic framework for an efficient oxygen evolution reaction by introducing minor atomically dispersed ruthenium

Carbon Energy, Journal Year: 2022, Volume and Issue: 5(2)

Published: Sept. 26, 2022

Abstract The establishment of efficient oxygen evolution electrocatalysts is great value but also challenging. Herein, a durable metal–organic framework (MOF) with minor atomically dispersed ruthenium and an optimized electronic structure constructed as electrocatalyst. Significantly, the obtained NiRu 0.08 ‐MOF doping Ru only needs overpotential 187 mV at 10 mA cm −2 Tafel slop 40 dec −1 in 0.1 M KOH for reaction, can work continuously more than 300 h. Ultrahigh mass activity achieved, reaching 56.7 A g 200 mV, which 36 times higher that commercial RuO 2 . X‐ray adsorption spectroscopy density function theory calculations reveal on metal sites MOFs expected to optimize nickel sites, thus improving conductivity catalyst optimizing energy intermediates, resulting significant optimization electrocatalytic performance. This study could provide new avenue design stable MOF electrocatalysts.

Language: Английский

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In Situ Synthesis of Chemically Bonded 2D/2D Covalent Organic Frameworks/O‐Vacancy WO₃ Z‐Scheme Heterostructure for Photocatalytic Overall Water Splitting

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(33)

Published: June 15, 2023

Abstract Covalent organic frameworks (COFs) have shown great promise for photocatalytic hydrogen evolution via water splitting. However, the four‐electron oxidation of remains elusive toward oxygen evolution. Enabling this pathway is critical to improve yield and maximize atom utilization efficiency. A Z‐scheme heterojunction proposed overcoming fundamental issues in COF‐based overall splitting (OWS), such as inefficient light absorption, charge recombination, poor ability. It that construction a novel 2D/2D through situ growth COFs on O‐vacancy WO 3 nanosheets (Ov‐WO ) WOC chemical bond can remarkably promote OWS. Benefiting from synergistic effect between enhanced built‐in electric field by interfacial bond, strong ability Ov‐WO 3, ultrathin structure TSCOF, both separation efficiency photogenerated electron–hole pairs be significantly enhanced. An impressive half‐rection rate 593 mmol h −1 g 146 (hydrogen) 68 (oxygen) µmol are achieved COF‐WO (TSCOFW) composite. This with two‐step excitation precisely cascaded charge‐transfer makes it responsible efficient solar‐driven OWS without sacrificial agent.

Language: Английский

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In Situ Growth of Covalent Organic Framework Nanosheets on Graphene as the Cathode for Long‐Life High‐Capacity Lithium‐Ion Batteries

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(37)

Published: July 29, 2022

The poor electronic and ionic conductivities of covalent organic frameworks (COFs) severely restrict the development COF-based electrodes for practical rechargeable batteries, therefore inspiring more research interest from direction both material synthesis technology. Herein, a dual-porous COF, USTB-6, with good crystallinity rich redox-active sites is conceived fabricated by polymerization 2,3,8,9,14,15-hexa(4-formylphenyl)diquinoxalino [2,3-a:2',3'-c]phenazine 2,7-diaminopyrene-4,5,9,10-tetraone. In particular, heterogeneous same starting materials in presence graphene affords uniformly dispersed COF nanosheets thickness 8.3 nm on conductive carbon substrate, effectively enhancing conductivity electrode. Such graphene-supported USTB-6 cathode when used lithium-ion battery exhibits specific capacity 285 mA h g-1 at current density 0.2 C excellent rate performance prominent 188 10 C. More importantly, 170 retained using after 6000 cycles charge discharge measurement 5

Language: Английский

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Porous crystalline materials for memories and neuromorphic computing systems

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(20), P. 7071 - 7136

Published: Jan. 1, 2023

This review highlights the film preparation methods and application advances in memory neuromorphic electronics of porous crystalline materials, involving MOFs, COFs, HOFs, zeolites.

Language: Английский

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Monolithic Covalent Organic Frameworks with Hierarchical Architecture: Attractive Platform for Contaminant Remediation

Chemistry of Materials, Journal Year: 2023, Volume and Issue: 35(7), P. 2661 - 2682

Published: March 24, 2023

The insolubility in solvents and poor processability of powder covalent organic frameworks (COFs) considerably impede their practical application. To address these issues bridge the gap between COFs application, construction monolithic has emerged as a feasible effective solution. Monolithic (i.e., macroscopic three-dimensional architectures) with hierarchical structures have attracted tremendous interest for environmental remediation exhibited good contaminant removal performances owing to wide distribution pore sizes ranging from micropores macropores, large specific surface area, tailored chemical components, excellent stability. can be either pure self-supporting or composites other materials. resulting COF-based monoliths inherit merits parent (such tunable size, structure, super chemical/thermal stability) intriguing features materials, such high porosity, easy handling, endowing them fast mass transfer adsorption capacity. This review provides comprehensive summary recent advances synthesis COF Additionally, progress application is summarized, including metal-ion removal, organic-pollutant capture, oil–water separation. Furthermore, this discusses current challenges future perspectives. We sincerely hope that it will contribute further development materials fields, especially remediation.

Language: Английский

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Modulating the Electronic Structures of Dual‐Atom Catalysts via Coordination Environment Engineering for Boosting CO₂Electroreduction

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(51)

Published: Nov. 1, 2022

Dual-atom catalysts (DACs) have emerged as efficient electrocatalysts for CO2 reduction owing to the synergistic effect between binary metal sites. However, rationally modulating electronic structure of DACs optimize catalytic performance remains a great challenge. Herein, we report modulation three Ni2 (namely, -N7 , -N5 C2 and -N3 C4 ) by regulation coordination environments around dual-atom centres. As result, exhibits significantly improved electrocatalytic activity reduction, not only better than corresponding single-atom Ni catalyst (Ni-N2 ), but also higher DACs. Density functional theory (DFT) calculations revealed that high could be attributed centre resulted proper binding energies COOH* CO* intermediates.

Language: Английский

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Self-supported electrocatalysts for the hydrogen evolution reaction

Materials Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 7(4), P. 567 - 606

Published: Dec. 15, 2022

The high-performance self-supported electrocatalysts for the hydrogen evolution reaction are systematically summarized.

Language: Английский

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