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Annihilator dimers enhance triplet fusion upconversion.

ABSTRACT: Optical upconversion is a net process by which two low energy photons are converted into one higher energy photon. There is vast potential to exploit upconversion in applications ranging from solar energy and biological imaging to data storage and photocatalysis. Here, we link two upconverting chromophores together to synthesize a series of novel tetracene dimers for use as annihilators. When compared with the monomer annihilator, TIPS-tetracene, the dimers yield a strong enhancement in the triplet fusion process, also known as triplet-triplet annihilation, as demonstrated via a large increase in upconversion efficiency and an order of magnitude reduction of the threshold power for maximum yield. Along with the ongoing rapid improvements to sensitizer materials, the dimerization improvements demonstrated here open the way to a wide variety of emerging upconversion applications.

SUBMITTER: Pun AB

PROVIDER: S-EPMC6457208 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Annihilator dimers enhance triplet fusion upconversion.

Pun Andrew B AB Sanders Samuel N SN Sfeir Matthew Y MY Campos Luis M LM Congreve Daniel N DN

Chemical science 20190307 14

Optical upconversion is a net process by which two low energy photons are converted into one higher energy photon. There is vast potential to exploit upconversion in applications ranging from solar energy and biological imaging to data storage and photocatalysis. Here, we link two upconverting chromophores together to synthesize a series of novel tetracene dimers for use as annihilators. When compared with the monomer annihilator, TIPS-tetracene, the dimers yield a strong enhancement in the trip ...[more]

PMID: 31015937

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