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Amorphous Carbon Dots and their Remarkable Ability to Detect 2,4,6-Trinitrophenol.

ABSTRACT: Apparently mundane, amorphous nanostructures of carbon have optical properties which are as exotic as their crystalline counterparts. In this work we demonstrate a simple and inexpensive mechano-chemical method to prepare bulk quantities of self-passivated, amorphous carbon dots. Like the graphene quantum dots, the water soluble, amorphous carbon dots too, exhibit excitation-dependent photoluminescence with very high quantum yield (~40%). The origin and nature of luminescence in these high entropy nanostructures are well understood in terms of the abundant surface traps. The photoluminescence property of these carbon dots is exploited to detect trace amounts of the nitro-aromatic explosive - 2,4,6-trinitrophenol (TNP). The benign nanostructures can selectively detect TNP over a wide range of concentrations (0.5 to 200?µM) simply by visual inspection, with a detection limit of 0.2?µM, and consequently outperform nearly all reported TNP sensor materials.

SUBMITTER: Siddique AB

PROVIDER: S-EPMC6021439 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Amorphous Carbon Dots and their Remarkable Ability to Detect 2,4,6-Trinitrophenol.

Siddique Abu Bakar AB Pramanick Ashit Kumar AK Chatterjee Subrata S Ray Mallar M

Scientific reports 20180627 1

Apparently mundane, amorphous nanostructures of carbon have optical properties which are as exotic as their crystalline counterparts. In this work we demonstrate a simple and inexpensive mechano-chemical method to prepare bulk quantities of self-passivated, amorphous carbon dots. Like the graphene quantum dots, the water soluble, amorphous carbon dots too, exhibit excitation-dependent photoluminescence with very high quantum yield (~40%). The origin and nature of luminescence in these high entro ...[more]

PMID: 29950660

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