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2D/0D graphene hybrids for visible-blind flexible UV photodetectors.

ABSTRACT: Nitrogen-functionalized graphene quantum dots (NGQDs) are attractive building blocks for optoelectronic devices because of their exceptional tunable optical absorption and fluorescence properties. Here, we developed a high-performance flexible NGQD/graphene field-effect transistor (NGQD@GFET) hybrid ultraviolet (UV) photodetector, using dimethylamine-functionalized GQDs (NMe₂-GQDs) with a large bandgap of ca. 3.3?eV. The NMe₂-GQD@GFET photodetector exhibits high photoresponsivity and detectivity of ca. 1.5?×?10⁴?A?W^-1 and ca. 5.5?×?10¹¹ Jones, respectively, in the deep-UV region as short as 255?nm without application of a backgate voltage. The feasibility of these flexible UV photodetectors for practical application in flame alarms is also demonstrated.

SUBMITTER: Tetsuka H

PROVIDER: S-EPMC5514071 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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2D/0D graphene hybrids for visible-blind flexible UV photodetectors.

Tetsuka Hiroyuki H

Scientific reports 20170717 1

Nitrogen-functionalized graphene quantum dots (NGQDs) are attractive building blocks for optoelectronic devices because of their exceptional tunable optical absorption and fluorescence properties. Here, we developed a high-performance flexible NGQD/graphene field-effect transistor (NGQD@GFET) hybrid ultraviolet (UV) photodetector, using dimethylamine-functionalized GQDs (NMe2-GQDs) with a large bandgap of ca. 3.3 eV. The NMe2-GQD@GFET photodetector exhibits high photorespon ...[more]

PMID: 28717126

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