Carbon dots-embedded fluorescent silica xerogel

Herein, we describe the dynamics of gel transition of silica sol (tetraethoxysilane (TEOS) in ethanol-H2O to xerogel viaoranogel route. Silica sol made in ethanolic solution turns into an organogel during sol-gel synthesis of TEOS, which eventually makes a phase transition to xerogel following a process of spontaneous dehydration of the gel network at room temperature. It was observed that the gelation time decreased with the increasing concentration of TEOS which was captured from dynamic light scattering profiling of the dynamics, and rheology. In order to tune and improve the functional properties, a nanocomposite xerogel was prepared by incorporating 5 nm size spherical and fluorescent carbon dots (CD) into the gel matrix. Presence of carbon dots significantly reduced both the organo-, and xero-gelation time. Carbon dots were able to impart fluorescence to these gels which may be used for bioimaging and real time tracking of drug delivery route.