Carbon quantum dots derived from pomegranate peel: highly effective Fe(III) sensor

Carbon quantum dots (CQDs), which have excellent photoluminescence properties, have been synthesized from pomegranate peel and sucrose as carbon sources by a hydrothermal method in this study. The reaction temperature and the synthesis time were optimized for obtaining CQDs with unique physical and chemical properties that can easily be soluble in water and show luminescence properties. The obtained CQDs were characterized by using thermogravimetric analysis (TGA), UV-Vis spectroscopy, fluorescence spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray diffractometry. The quantum yield (QY) of the synthesized CQDs was calculated as 7.02%. The obtained CQDs exhibited highly selective sensor properties and detected Fe3+ ions in Co2+, Al3+, Hg2+, Cu2+, Zn2+, Ni2+, Ba2+, Mn2+, Li+, K+, and Fe2+ cations at the same concentration. Fe(III) ions can be detected at 7.488 mu M concentration with R-2 = 0.952 value. The sensitivity performance of the obtained CQDs was also evaluated in different types of real water samples. It was also determined the synthesized carbon quantum dots were very sensitive to Fe3+ in well water (CQDs-W), seawater (CQDs-Sea), dam water (CQDs-D), tap water (CQDs-T), snow water (CQDs-Snow), and ultrapure water (CQDs-U) as nearly the same in the pure water samples under ideal environments that quenched the fluorescence intensity of CQDs.