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An insight into non-emissive excited states in conjugated polymers.

ABSTRACT: Conjugated polymers in the solid state usually exhibit low fluorescence quantum yields, which limit their applications in many areas such as light-emitting diodes. Despite considerable research efforts, the underlying mechanism still remains controversial and elusive. Here, the nature and properties of excited states in the archetypal polythiophene are investigated via aggregates suspended in solvents with different dielectric constants (?). In relatively polar solvents (?>? 3), the aggregates exhibit a low fluorescence quantum yield (QY) of 2-5%, similar to bulk films, however, in relatively nonpolar solvents (?

SUBMITTER: Hu Z

PROVIDER: S-EPMC4595598 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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An insight into non-emissive excited states in conjugated polymers.

Hu Zhongjian Z Willard Adam P AP Ono Robert J RJ Bielawski Christopher W CW Rossky Peter J PJ Vanden Bout David A DA

Nature communications 20150922

Conjugated polymers in the solid state usually exhibit low fluorescence quantum yields, which limit their applications in many areas such as light-emitting diodes. Despite considerable research efforts, the underlying mechanism still remains controversial and elusive. Here, the nature and properties of excited states in the archetypal polythiophene are investigated via aggregates suspended in solvents with different dielectric constants (ɛ). In relatively polar solvents (ɛ>∼ 3), the aggregates e ...[more]

PMID: 26391514

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