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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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Reaction induced morphology changes of tetracene and pentacene surfaces
Morphology plays a critical role in determining the properties of solid-state molecular materials, yet fluctuates wildly as these materials undergo reaction. A prototypical system, a vapor–solid Diels–Alder reaction of tetracene and pentacene thin-films, is used to observe the evolution of morphology features as the reaction transitions from surface to bulk. The initial stages of reaction display little topographical change as measured by atomic force microscopy (AFM) and scanning electron microscopy (SEM), and substrates are coated with a uniform layer of product 1–2 molecules thick, as determined by energy-dispersive X-ray (EDX) spectroscopy. The highly textured surfaces of late stage reactions are a result of aggregated products, as identified via EDX spectroscopy and polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS); areas of the surface in between product aggregates resemble the initial stages. The mechanism by which products aggregate into surface asperities requires the assistance of a facilitating media – in this case condensed vapor; simple thermally assisted surface diffusion was unable to generate these morphology changes. The combined data indicate that reactions of molecular solids, could be confined to the surface in the absence of condensate of the vapor phase reactant.
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- PAR ID:
- 10173231
- Date Published:
- Journal Name:
- RSC Advances
- Volume:
- 9
- Issue:
- 46
- ISSN:
- 2046-2069
- Page Range / eLocation ID:
- 26942 to 26948
- 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/10.1039/C9RA05682C
