OPTICAL PROPERTIES OF COLLOIDAL SOLUTIONS OF CARBON DOTS

Abstract

In this work, optical properties of carbon dots (CDs) chemically synthesized by solvothermal carbonization of a mixture of urea and anhydrous citric acid were studied. Size distribution of CDs with a typical chemical structure was estimated from dynamic light scattering. Absorption, fluorescence excitation/emission spectra as well as characteristic fluorescence lifetimes were measured. An energy diagram of photostimulated electronic transitions in this type of multicolor fluorescent carbon nanoparticles was also proposed. Temperature dependence of the PL/PLE-maps of CDs colloids in the range of 5‒75 ° C was measured and it demonstrates the possibility of their use for thermometry purposes. We also showed a possibility of CDs using for multicolor cell fluorescence imaging.