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Triplet energy migration-based photon upconversion by amphiphilic molecular assemblies in aerated water.

ABSTRACT: A molecular self-assembly approach is developed to resolve an outstanding issue in triplet energy migration-based photon upconversion (TEM-UC), that is, air-stable TEM-UC in water. Amphiphilic cationic acceptor (emitter) molecules self-assemble in water via hydrophobic and hydrogen bonding interactions, with which anionic donor (sensitizer) molecules are integrated through electrostatic interactions. Triplet energy is quantitatively transferred from the excited donor to the acceptor, which is followed by effective triplet energy migration among the pre-organized acceptors. It leads to TTA and concomitant UC emission in water. The dense acceptor chromophore arrays with extended hydrogen bonding networks show efficient barrier properties against molecular oxygen, as demonstrated by the stable UC emission even in air-saturated water.

SUBMITTER: Kouno H

PROVIDER: S-EPMC6020542 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Triplet energy migration-based photon upconversion by amphiphilic molecular assemblies in aerated water.

Kouno Hironori H Ogawa Taku T Amemori Shogo S Mahato Prasenjit P Yanai Nobuhiro N Kimizuka Nobuo N

Chemical science 20160418 8

A molecular self-assembly approach is developed to resolve an outstanding issue in triplet energy migration-based photon upconversion (TEM-UC), that is, air-stable TEM-UC in water. Amphiphilic cationic acceptor (emitter) molecules self-assemble in water <i>via</i> hydrophobic and hydrogen bonding interactions, with which anionic donor (sensitizer) molecules are integrated through electrostatic interactions. Triplet energy is quantitatively transferred from the excited donor to the acceptor, whic ...[more]

PMID: 30155172

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