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Abstract A simple and environmentally benign technology for synthesizing ultrasmall CuInanoparticles (NPs) on the surface of the food additive hydroxypropyl methylcellulose (HPMC) and their application in completely organic solvent‐free tandem alkyne‐azide cycloaddition reactions were reported. The NP catalyst was thoroughly characterized by high‐angle annular dark‐field scanning transmission electron microscopy, high‐resolution transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, and X‐ray photoelectron spectroscopy analysis for its morphology, particle size distribution, chemical composition, and oxidation state analyses. The NP catalyst was highly efficient, affording products in 10–45 min. All products were obtained in high purity by simple filtration, obviating organic solvents from the reaction set‐up to product isolation. The methodology is general and scalable as validated by a broad substrate scope.
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Nanoscale and ultrafast in situ techniques to probe plasmon photocatalysis
Plasmonic photocatalysis uses the light-induced resonant oscillation of free electrons in a metal nanoparticle to concentrate optical energy for driving chemical reactions. By altering the joint electronic structure of the catalyst and reactants, plasmonic catalysis enables reaction pathways with improved selectivity, activity, and catalyst stability. However, designing an optimal catalyst still requires a fundamental understanding of the underlying plasmonic mechanisms at the spatial scales of single particles, at the temporal scales of electron transfer, and in conditions analogous to those under which real reactions will operate. Thus, in this review, we provide an overview of several of the available and developing nanoscale and ultrafast experimental approaches, emphasizing those that can be performed in situ. Specifically, we discuss high spatial resolution optical, tip-based, and electron microscopy techniques; high temporal resolution optical and x-ray techniques; and emerging ultrafast optical, x-ray, tip-based, and electron microscopy techniques that simultaneously achieve high spatial and temporal resolution. Ab initio and classical continuum theoretical models play an essential role in guiding and interpreting experimental exploration, and thus, these are also reviewed and several notable theoretical insights are discussed.
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- Award ID(s):
- 2413590
- PAR ID:
- 10532651
- Publisher / Repository:
- AIP Publishing
- Date Published:
- Journal Name:
- Chemical Physics Reviews
- Volume:
- 4
- Issue:
- 4
- ISSN:
- 2688-4070
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/5.0163354
