SYNTHESIS AND CHARACTERIZATION OF pH SENSITIVE CARBON DOTS FROM TEA

Abstract

Carbon dots are new series of fluorescent nanomaterials that have drawn great attention in recent years owing to their unique properties. In this project, a simple green approach to synthesize carbon dots was developed by using tea powder as the carbon precursor. The synthesized carbon dots were further characterized using PL spectra. The effect of pH on the PL spectra of carbon dots was also analysed.. The alcoholic solution of as-prepared carbon dots were nearly transparent under visible light, while it displayed strong blue fluorescence under UV light (310nm). The PL spectra shows when excited at the maximum excitation wavelength of 375nm, the as-prepared carbon dots exhibited a strong PL peak at 470nm.In strong acidic condition, the emission wavelength shift to the 510nm wavelength, while it moved to 493nm wavelength in strong basic solution, implying that the as-prepared carbon dots were very sensitive to pH. So the carbon dots can be used as a promising material for sensing, bio imaging etc.