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Control over size, shape, and photonics of self-assembled organic nanocrystals.

ABSTRACT: The facile fabrication of free-floating organic nanocrystals (ONCs) was achieved via the kinetically controlled self-assembly of simple perylene diimide building blocks in aqueous medium. The ONCs have a thin rectangular shape, with an aspect ratio that is controlled by the content of the organic cosolvent (THF). The nanocrystals were characterized in solution by cryogenic transmission electron microscopy (cryo-TEM) and small-angle X-ray scattering. The ONCs retain their structure upon drying, as was evidenced by TEM and atom force microscopy. Photophysical studies, including femtosecond transient absorption spectroscopy, revealed a distinct influence of the ONC morphology on their photonic properties (excitation energy transfer was observed only in the high-aspect ONCs). Convenient control over the structure and function of organic nanocrystals can enhance their utility in new and developed technologies.

SUBMITTER: Shahar C

PROVIDER: S-EPMC7801800 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Control over size, shape, and photonics of self-assembled organic nanocrystals.

Shahar Chen C Tidhar Yaron Y Jung Yunmin Y Weissman Haim H Cohen Sidney R SR Bitton Ronit R Pinkas Iddo I Haran Gilad G Rybtchinski Boris B

Beilstein journal of organic chemistry 20210106

The facile fabrication of free-floating organic nanocrystals (ONCs) was achieved via the kinetically controlled self-assembly of simple perylene diimide building blocks in aqueous medium. The ONCs have a thin rectangular shape, with an aspect ratio that is controlled by the content of the organic cosolvent (THF). The nanocrystals were characterized in solution by cryogenic transmission electron microscopy (cryo-TEM) and small-angle X-ray scattering. The ONCs retain their structure upon drying, a ...[more]

PMID: 33488830

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