Fig. 2
a Normalized PL spectra of NCDs in six solvents, λex = 400 nm. b Digital photograph of NCDs in six solvents under an UV lamp. c Absorption spectra of NCDs in six solvents. Relationship between the spectral parameters and ET (30): d Stokes shifts and e lifetimes. f Schematic illustration of the interaction between surface functional groups and solvents. Solvents used are as follows. 1: toluene, 2: acetone, 3: DMSO, 4: ethanol, 5: EG, 6: water