Facile and Green synthesis of fluorescent N-doped carbon dots from betel leaves for sensitive detection of Picric acid and Iron ion

Abstract

In this present work, a facile, green, cost effective route has been applied for the synthesis of water soluble carbon dots from betel leaves by hydrothermal route. As obtained nitrogen doped carbon dots (N-CDs) show remarkable advantages such as water solubility, biocompatibility and excellent stability. It is analyzed by vital characterization techniques such as HR-TEM, AFM, PSA, XRD, XPS, FTIR, UV-–vis and fluorescence spectroscopy with lifetime analysis. It exhibits blue emission under UV lamp (wavelength 365 nm), excitation dependent emission behavior and independent of pH. The obtained N-CDs show excellent response to picric acid (PA) and Fe3+ ions which leads to fluorescence quenching. This phenomenon was applied to design a single probe fluorescence based system for dual detection with high selectivity and sensitivity. A good linear response was obtained between concentration of analyte and fluorescence intensity with limit of detection (LOD) 0.11μM in the range of 0.3−3.3μM for PA and 0.135μM in the range of 0.3−3.3μM for Fe3+. Finally, the obtained fluorescent probe could be a promising tool for sensitive detection of PA and Fe3+ in aqueous solution.