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Abstract Photothermal CO2reduction is one of the most promising routes to efficiently utilize solar energy for fuel production at high rates. However, this reaction is currently limited by underdeveloped catalysts with low photothermal conversion efficiency, insufficient exposure of active sites, low active material loading, and high material cost. Herein, we report a potassium‐modified carbon‐supported cobalt (K+−Co−C) catalyst mimicking the structure of a lotus pod that addresses these challenges. As a result of the designed lotus‐pod structure which features an efficient photothermal C substrate with hierarchical pores, an intimate Co/C interface with covalent bonding, and exposed Co catalytic sites with optimized CO binding strength, the K+−Co−C catalyst shows a record‐high photothermal CO2hydrogenation rate of 758 mmol gcat−1 h−1(2871 mmol gCo−1 h−1) with a 99.8 % selectivity for CO, three orders of magnitude higher than typical photochemical CO2reduction reactions. We further demonstrate with this catalyst effective CO2conversion under natural sunlight one hour before sunset during the winter season, putting forward an important step towards practical solar fuel production.
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Templating and Catalyzing [2+2] Photocycloaddition in Solution Using a Dynamic G‐Quadruplex
Abstract We describe a templating/covalent capture strategy that enables photochemical formation of 8 cyclobutanes in one noncovalent assembly. This process was characterized by experiment and quantum mechanical/molecular mechanics (ONIOM) calculations. Thus, KI and 16 units of 5′‐cinnamate guanosine form a G‐quadruplex where C=C π bonds in neighboring G4‐quartets are separated by 3.3 Å, enabling [2+2] photocycloaddition in solution. This reaction is high‐yielding (>90 %), regio‐ and diastereoselective. Since all components are in dynamic equilibrium this photocycloaddition is catalytic in K+.
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- Award ID(s):
- 1751568
- PAR ID:
- 10080219
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 52
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 17146-17150
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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