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Raman Enhancement and Photo-Bleaching of Organic Dyes in the Presence of Chemical Vapor Deposition-Grown Graphene.

ABSTRACT: Fluorescent organic dyes photobleach under intense light. Graphene has been shown to improve the photo-stability of organic dyes. In this paper, we investigated the Raman spectroscopy and photo-bleaching kinetics of dyes in the absence/presence of chemical vapor deposition (CVD)-grown graphene. We show that graphene enhances the Raman signal of a wide range of dyes. The photo-bleaching of the dyes was reduced when the dyes were in contact with graphene. In contrast, monolayer hexagonal boron nitride (h-BN) was much less effective in reducing the photo-bleaching rate of the dyes. We attribute the suppression of photo-bleaching to the energy or electron transfer from dye to graphene. The results highlight the potential of CVD graphene as a substrate for protecting and enhancing Raman response of organic dyes.

SUBMITTER: Weng J

PROVIDER: S-EPMC5666502 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Raman Enhancement and Photo-Bleaching of Organic Dyes in the Presence of Chemical Vapor Deposition-Grown Graphene.

Weng Jiaxin J Zhao Shichao S Li Zhiting Z Ricardo Karen B KB Zhou Feng F Kim Hyojeong H Liu Haitao H

Nanomaterials (Basel, Switzerland) 20171019 10

Fluorescent organic dyes photobleach under intense light. Graphene has been shown to improve the photo-stability of organic dyes. In this paper, we investigated the Raman spectroscopy and photo-bleaching kinetics of dyes in the absence/presence of chemical vapor deposition (CVD)-grown graphene. We show that graphene enhances the Raman signal of a wide range of dyes. The photo-bleaching of the dyes was reduced when the dyes were in contact with graphene. In contrast, monolayer hexagonal boron nit ...[more]

PMID: 29048349

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