Optically active carbon nanodot—A facile platform for the selective sensing of chromium (VI) ion.

The fabrication of a facile matrix is necessary for the detection of metal ions due to their hazardous deed on environment. Present study reports the synthesis and characterisation of optically active carbon nanodot and their application towards chromium (VI) ion sensing. Simple, facile and green method was used for the synthesis of undoped (CND) as well as nitrogen doped carbon nanodot (NCND). As synthesised CND and NCND were characterized by Transmission Electron Microscopic (TEM) technique, Fourier Transform Infrared spectroscopic (FT-IR) technique, UV- Visible absorption spectroscopy and Photoluminescence spectroscopy. The average size of CND was found to be 7nm and it was amorphous in nature. The synthesised CND as well as NCND were optically active. The nanodots exhibited excitation dependent fluorescence with maximum emission peak centered at 463nm and 464nm for CND and NCND respectively with the corresponding excitation. NCND exhibited higher fluorescent intensity compared to the undoped counterparts. Moreover, the fluorescence of NCND was quenched by the addition of chromium (VI) ion in it. The synthesised NCND was effectively used as a selective turn off sensor of chromium (VI) metal ion with detection limit of 9mM. [ABSTRACT FROM AUTHOR]