Linking oxidative and reductive clusters to prepare crystalline porous catalysts for photocatalytic CO2 reduction with H2O

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Авг. 10, 2022

Mimicking natural photosynthesis to convert CO2 with H2O into value-added fuels achieving overall reaction is a promising way reduce the atmospheric level. Casting catalyst of two or more catalytic sites rapid electron transfer and interaction may be an effective strategy for coupling photocatalytic reduction oxidation. Herein, based on MOF ∪ COF collaboration, we have carefully designed synthesized crystalline hetero-metallic cluster denoted MCOF-Ti6Cu3 spatial separation functional cooperation between oxidative reductive clusters. It utilizes dynamic covalent bonds clusters promote photo-induced charge efficiency, drive both reactions. exhibits fine activity in conversion water HCOOH (169.8 μmol g-1h-1). Remarkably, experiments theoretical calculations reveal that photo-excited electrons are transferred from Ti Cu, indicating Cu center.

Язык: Английский

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Tuning excited state electronic structure and charge transport in covalent organic frameworks for enhanced photocatalytic performance

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Фев. 27, 2023

Covalent organic frameworks (COFs) represent an emerging class of photocatalysts. However, their complicated structures lead to indeterminacy about photocatalytic active sites and reaction mechanisms. Herein, we use reticular chemistry construct a family isoreticular crystalline hydrazide-based COF photocatalysts, with the optoelectronic properties local pore characteristics COFs modulated using different linkers. The excited state electronic distribution transport pathways in are probed host experimental methods theoretical calculations at molecular level. One our developed (denoted as COF-4) exhibits remarkable electron utilization efficiency charge transfer properties, achieving record-high uranium extraction performance ~6.84 mg/g/day natural seawater among all techniques reported so far. This study brings new understanding operation COF-based guiding design improved photocatalysts for many applications.

Язык: Английский

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In situ photodeposition of platinum clusters on a covalent organic framework for photocatalytic hydrogen production

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Март 15, 2022

Photocatalytic hydrogen production has been considered a promising approach to obtain green energy. Crystalline porous materials have arisen as key photocatalysts for efficient production. Here, we report strategy in situ photodeposit platinum clusters cocatalyst on covalent organic framework, which makes it an photocatalyst light-driven evolution. Periodically dispersed adsorption sites of species are constructed by introducing adjacent hydroxyl group and imine-N the region framework structural unit where photogenerated electrons converge, leading reduction adsorbed into metal electrons. The widespread expose large active surface greatly facilitate electron transfer, finally contributing high photocatalytic evolution rate 42432 μmol g-1 h-1 at 1 wt% loading. This work provides direction design frameworks precisely manipulate morphologies positions atomic level developing photocatalysts.

Язык: Английский

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Three-Component Donor−π–Acceptor Covalent–Organic Frameworks for Boosting Photocatalytic Hydrogen Evolution

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(15), С. 8364 - 8374

Опубликована: Март 14, 2023

Two-dimensional covalent-organic frameworks (2D COFs) have recently emerged as great prospects for their applications new photocatalytic platforms in solar-to-hydrogen conversion; nevertheless, inefficient solar energy capture and fast charge recombination hinder the improvement of hydrogen production performance. Herein, two photoactive three-component donor-π-acceptor (TCDA) materials were constructed using a multicomponent synthesis strategy by introducing electron-deficient triazine electron-rich benzotrithiophene moieties into through sp2 carbon imine linkages, respectively. Compared with two-component COFs, novel TCDA-COFs are more convenient regulating inherent photophysical properties, thereby realizing outstanding activity evolution from water. Remarkably, first carbon-linked TCDA-COF displays an impressive rate 70.8 ± 1.9 mmol g-1 h-1 excellent reusability presence 1 wt % Pt under visible-light illumination (420-780 nm). Utilizing combination diversified spectroscopy theoretical prediction, we show that full π-conjugated linkage not only effectively broadens harvesting COFs but also enhances transfer separation efficiency.

Язык: Английский

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Covalent organic frameworks for photocatalysis: Synthesis, structural features, fundamentals and performance

Coordination Chemistry Reviews, Год журнала: 2022, Номер 475, С. 214889 - 214889

Опубликована: Окт. 15, 2022

Язык: Английский

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Computation-based regulation of excitonic effects in donor-acceptor covalent organic frameworks for enhanced photocatalysis

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Май 29, 2023

The strong excitonic effects widely exist in polymer-semiconductors and the large exciton binding energy (Eb) seriously limits their photocatalysis. Herein, density functional theory (DFT) calculations are conducted to assess band alignment charge transfer feature of potential donor-acceptor (D-A) covalent organic frameworks (COFs), using 1,3,5-tris(4-aminophenyl)triazine (TAPT) or 1,3,5-tris(4-aminophenyl)benzene (TAPB) as acceptors tereph-thaldehydes functionalized diverse groups donors. Given discernable D-A interaction strengths pairs, Eb can be systematically regulated with minimum TAPT-OMe. Guided by these results, corresponding COFs synthesized, where TAPT-OMe-COF possesses best activity photocatalytic H2 production trend other is associated that calculated for pairs. In addition, further alkyne cycloaddition imine linkage greatly improves stability resulting TAPT-OMe-alkyne-COF a substantially smaller exhibits ~20 times higher than parent COF.

Язык: Английский

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Tuning Local Charge Distribution in Multicomponent Covalent Organic Frameworks for Dramatically Enhanced Photocatalytic Uranium Extraction

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(30)

Опубликована: Апрель 29, 2023

Optimizing the electronic structure of covalent organic framework (COF) photocatalysts is essential for maximizing photocatalytic activity. Herein, we report an isoreticular family multivariate COFs containing chromenoquinoline rings in COF and electron-donating or withdrawing groups pores. Intramolecular donor-acceptor (D-A) interactions allowed tuning local charge distributions carrier separation under visible light irradiation, resulting enhanced performance. By optimizing optoelectronic properties COFs, a uranium extraction efficiency 8.02 mg/g/day was achieved using nitro-functionalized multicomponent natural seawater, exceeding performance all reported to date. Results demonstrate effective design strategy towards high-activity with intramolecular D-A structures not easily accessible traditional synthetic approaches.

Язык: Английский

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Constructing Synergistic Triazine and Acetylene Cores in Fully Conjugated Covalent Organic Frameworks for Cascade Photocatalytic H₂O₂ Production

Chemistry of Materials, Год журнала: 2022, Номер 34(11), С. 5232 - 5240

Опубликована: Май 16, 2022

Covalent organic frameworks (COFs) are an ideal template for photocatalytic H2O2 synthesis because of the tunable chemical structures and semiconductor properties. However, photoactivity COFs is still under-improved due to inefficient intrinsic charge generation, fast recombination photogenerated charges, limited electron transport along frameworks. Herein, spatially separated synergistic triazine acetylene units first integrated into (EBA-COF BTEA-COF) production. The spatial separation cores leads efficient suppressed recombination, C═C linkage facilitates electrons over skeletons. Both experimental computational results suggested that synergistically promote in a two-electron pathway. EBA-COF showed attractive activity with production rate 1830 μmol h–1 gcat–1, superior most other COF-based catalysts. This study provides method designing photocatalysts active sites based on vinylene-linked COFs.

Язык: Английский

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Covalent Organic Frameworks for Energy Conversion in Photocatalysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(34)

Опубликована: Апрель 24, 2023

Abstract Intensifying energy crises and severe environmental issues have led to the discovery of renewable sources, sustainable conversion, storage technologies. Photocatalysis is a green technology that converts eco‐friendly solar into high‐energy chemicals. Covalent organic frameworks (COFs) are porous materials constructed by covalent bonds show promising potential for converting chemicals owing their pre‐designable structures, high crystallinity, porosity. Herein, we highlight recent progress in synthesis COF‐based photocatalysts applications water splitting, CO 2 reduction, H O production. The challenges future opportunities rational design COFs advanced discussed. This Review expected promote further development toward photocatalysis.

Язык: Английский

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Thiophene‐Containing Covalent Organic Frameworks for Overall Photocatalytic H₂O₂ Synthesis in Water and Seawater

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(38)

Опубликована: Авг. 1, 2023

H2 O2 is a significant chemical widely utilized in the environmental and industrial fields, with growing global demand. Without sacrificial agents, simultaneous photocatalyzed synthesis through oxygen reduction reaction (ORR) water oxidation (WOR) dual channels from seawater green sustainable but still challenging. Herein, two novel thiophene-containing covalent organic frameworks (TD-COF TT-COF) were first constructed served as catalysts for via indirect 2e- ORR direct WOR channels. The photocatalytic production performance can be regulated by adjusting N-heterocycle modules (pyridine triazine) COFs. Notably, no just using air raw materials, TD-COF exhibited high yields of 4060 μmol h-1 g-1 3364 deionized natural seawater, respectively. Further computational mechanism studies revealed that thiophene was primary photoreduction unit ORR, while benzene ring (linked to imine bond) central photooxidation WOR. current work exploits COFs overall provides fresh insight into creating innovative photocatalyzing synthesis.

Язык: Английский

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