One-step microwave-assisted green synthesis of luminescent N-doped carbon dots from sesame seeds for selective sensing of Fe(III)

The present study focuses on the green synthesis of nitrogen-doped carbon dots (C. dots) from sesame seeds using microwave pyrolysis method. The C. dots obtained were characterized and extensively studied using transmission electron microscopy (TEM), UV/visible spectroscopy, fluorescence spectroscopy and Fourier transform infra-red spectroscopy (FTIR) techniques. The results indicated the presence of highly fluorescent, aqueous soluble and significantly photostable C. dots with a quantum yield of 8.02%. The average size distributions of C. dots were found to be 5 nm. These C. dots were effectively applied as a selective sensor for Fe(III) as the fluorescence intensity was significantly quenched with increasing metal concentrations. The limit of detection (LOD) was found to be 2.56. M of Fe(III). This study demonstrates a low cost, environmental friendly and waste recyclable synthetic method for preparation of C. dots and its application as a selective Fe(III) sensor.