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Bright long-lived luminescence of silicon nanocrystals sensitized by two-photon absorbing antenna.

ABSTRACT: Silicon nanocrystals of the average diameter of 5 nm, functionalized with 4,7-di(2-thienyl)-2,1,3-benzothiadiazole chromophores (TBT) and dodecyl chains, exhibit near-infrared emission upon one-photon (1P) excitation at 515 nm and two-photon (2P) excitation at 960 nm. By using TBT chromophores as an antenna we were able to enhance both 1P and 2P absorption cross-sections of the silicon nanocrystals to more efficiently excite their long-lived luminescence. These results chart a path to two-photon-excitable imaging probes with long-lived oxygen-independent luminescence - a rare combination of properties that should allow for a substantial increase in imaging contrast.

SUBMITTER: Ravotto L

PROVIDER: S-EPMC5619661 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Bright long-lived luminescence of silicon nanocrystals sensitized by two-photon absorbing antenna.

Ravotto Luca L Chen Qi Q Ma Yuguo Y Vinogradov Sergei A SA Locritani Mirko M Bergamini Giacomo G Negri Fabrizia F Yu Yixuan Y Korgel Brian A BA Ceroni Paola P

Chem 20170401 4

Silicon nanocrystals of the average diameter of 5 nm, functionalized with 4,7-di(2-thienyl)-2,1,3-benzothiadiazole chromophores (<b>TBT</b>) and dodecyl chains, exhibit near-infrared emission upon one-photon (1P) excitation at 515 nm and two-photon (2P) excitation at 960 nm. By using <b>TBT</b> chromophores as an antenna we were able to enhance both 1P and 2P absorption cross-sections of the silicon nanocrystals to more efficiently excite their long-lived luminescence. These results chart a path ...[more]

PMID: 28966989

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Dataset Information

Bright long-lived luminescence of silicon nanocrystals sensitized by two-photon absorbing antenna.

Publications

Bright long-lived luminescence of silicon nanocrystals sensitized by two-photon absorbing antenna.

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