| 1. |
- Li, Zhuwei, et al.
(författare)
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Engineering single-atom active sites anchored covalent organic frameworks for efficient metallaphotoredox C-N cross-coupling reactions
- 2022
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Ingår i: Science Bulletin. - : Elsevier BV. - 2095-9273. ; 67:19, s. 1971-1981
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Tidskriftsartikel (refereegranskat)abstract
- Photoredox catalysis has become an indispensable solution for the synthesis of small organic molecules. However, the precise construction of single-atomic active sites not only determines the catalytic performance, but also avails the understanding of structure-activity relationship. Herein, we develop a facile approach to immobilize single-atom Ni sites anchored porous covalent organic framework (COF) by use of 4,40,400-(1,3,5-triazine-2,4,6-triyl)trianiline and 2,6-diformylpyridine (Ni SAS/TD-COF). Ni SAS/TDCOF catalyst achieves excellent catalytic performance in visible-light-driven catalytic carbon-nitrogen cross-coupling reaction between aryl bromides and amines under mild conditions. The reaction provides amine products in excellent yields (71%-97%) with a wide range of substrates, including aryl and heteroaryl bromides with electron-deficient, electron-rich and neutral groups. Notably, Ni SAS/TD-COF could be recovered from the reaction mixture, corresponding to the negligible loss of photoredox performance after several cycles. This work provides a promising opportunity upon rational design of single-atomic active sites on COFs and the fundamental insight of photoredox mechanism for sustainable organic transformation.
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| 2. |
- Li, Zhuwei, et al.
(författare)
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Integrated nickel/polymer dual catalytic system for visible-light-driven sulfonamidation between aryl halides and aryl sulfonamides
- 2022
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Ingår i: CHEM CATALYSIS. - : Elsevier BV. - 2667-1093. ; 2:12, s. 3546-3558
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Tidskriftsartikel (refereegranskat)abstract
- By merging transition metal and heterogeneous photocatalyst, a metal-photoredox system has attracted more attention for cross -coupling of various dual photoredox catalysis. However, there is a grand challenge for the attenuated nucleophilicity of sulfonamides relative to alkyl amines. Herein, an integrated dual catalytic system of porous carbon nitride nanosheet with nitrogen vacancies (NV-P-C3N4)as a conjugated polymer semiconductor host in combination with transition-metal nickel (Ni) was constructed by a defect and morphology regulation strategy toward visible-light-driven sulfona-midation between aryl halides and aryl sulfonamides. The excellent nickel/photoredox-catalyzed C-N coupling reaction performance is ascribed to the large specific surface area, abundant active sites, long carrier lifetime, and efficient transfer and separation of photo -excited electrons and holes. This work highlights the opportunity to cooperate with heterogeneous catalysts and active metal sites for challenging cross-coupling reactions.
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| 3. |
- Shao, Teng, et al.
(författare)
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A chemically bonded and plasmonic Z-scheme junction for high-performance artificial photosynthesis of hydrogen peroxide
- 2022
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Ingår i: Journal of Materials Chemistry A. - : Royal Society of Chemistry (RSC). - 2050-7488 .- 2050-7496. ; 11:3, s. 1199-1207
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Tidskriftsartikel (refereegranskat)abstract
- Artificial photosynthesis has been regarded as a promising solution for the clean, sustainable, and efficient production of hydrogen peroxide (H2O2). However, rigorous regulation of light absorption, charge transfer, and surface kinetics is significant for catalytic performance. As a proof of concept, we report a chemically bonded and plasmonic Z-scheme junction as a model material prepared by the in situ assembly of nonstoichiometric W18O49 (WO) onto two-dimensional carbon nitride nanosheets (CNs) for high-performance artificial photosynthesis of H2O2. Notably, this typical Z-scheme photocatalyst exhibits the highest H2O2 generation rate of 732.4 μmol g−1 h−1, higher than that of individual catalysts, even maintaining 140.5 μmol g−1 h−1 under broad-spectrum response irradiation (λ > 700 nm). From the analysis of experimental characterization and density functional theory calculations, the superior performance of CN/WO heterostructures is ascribed to an intense localized surface plasmon resonance absorption, appropriate band alignment, and strong internal electric field. This work not only elucidates the key role of chemically bonded and plasmonic heterostructures but also paves an avenue for the rational design and construction of Z-scheme photocatalysts for solar energy conversion.
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| 4. |
- Zhang, Bo, et al.
(författare)
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Rational design of bismuth-based catalysts for electrochemical CO2 reduction
- 2022
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Ingår i: Cuihuà xuébào. - : Elsevier BV. - 0253-9837 .- 1872-2067. ; 43:12, s. 3062-3088
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Forskningsöversikt (refereegranskat)abstract
- Sustainable conversion of carbon dioxide (CO2) to high value-added chemicals and fuels is a promising solution to solve the problem of excessive CO2 emissions and alleviate the shortage of fossil fuels, maintaining the balance of the carbon cycle in nature. The development of catalytic system is of great significance to improve the efficiency and selectivity for electrochemical CO2 conversion. In particular, bismuth (Bi) based catalysts are the most promising candidates, while confronting challenges. This review aims to elucidate the fundamental issues of efficient and stable Bi-based catalysts, constructing a bridge between the category, synthesis approach and electrochemical performance. In this review, the categories of Bi-based catalysts are firstly introduced, such as metals, alloys, single atoms, compounds and composites. Followed by the statement of the reliable and versatile synthetic approaches, the representative optimization strategies, such as morphology manipulation, defect engineering, component and heterostructure regulation, have been highlighted in the discussion, paving in-depth insight upon the design principles, reaction activity, selectivity and stability. Afterward, in situ characterization techniques will be discussed to illustrate the mechanisms of electrochemical CO2 conversion. In the end, the challenges and perspectives are also provided, promoting a systematic understanding in terms of the bottleneck and opportunities in the field of electrochemical CO2 conversion. Published by Elsevier B.V. All rights reserved.
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