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Revealing the influence of steric bulk on the triplet-triplet annihilation upconversion performance of conjugated polymers.

ABSTRACT: A series of poly(phenylene-vinylene)-based copolymers are synthesized using the Gilch method incorporating monomers with sterically bulky sidechains. The photochemical upconversion performance of these polymers as emitters are investigated using a palladium tetraphenyltetrabenzoporphyrin triplet sensitizer and MEH-PPV as reference. Increased incorporation of sterically bulky monomers leads to a reduction in the upconversion efficiency despite improved photoluminescence quantum yield. A phosphorescence quenching study indicates issues with the energy transfer process between the triplet sensitizer and the copolymers. The best performance with 0.18% upconversion quantum yield is obtained for the copolymer containing 10% monomer with bulky sidechains.

SUBMITTER: O'shea R

PROVIDER: S-EPMC8486830 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Revealing the influence of steric bulk on the triplet-triplet annihilation upconversion performance of conjugated polymers.

O'shea Riley R Kendrick William J WJ Gao Can C Owyong Tze Cin TC White Jonathan M JM Ghiggino Kenneth P KP Wong Wallace W H WWH

Scientific reports 20211001 1

A series of poly(phenylene-vinylene)-based copolymers are synthesized using the Gilch method incorporating monomers with sterically bulky sidechains. The photochemical upconversion performance of these polymers as emitters are investigated using a palladium tetraphenyltetrabenzoporphyrin triplet sensitizer and MEH-PPV as reference. Increased incorporation of sterically bulky monomers leads to a reduction in the upconversion efficiency despite improved photoluminescence quantum yield. A phosphore ...[more]

PMID: 34599257

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