UV–vis absorption, PL emission spectra, AFM height images, and section analysis of carbon dots. (a) UV–vis absorption of carbon dots-NH2. (b) Photoluminescence emission spectra of carbon dots with progressively excitation wavelength from 320 to 400 nm in 10-nm increment; inset is the solution illuminated with a UV lamp, (c) AFM height images of carbon dots. (d) The section analysis of carbon dots.
Gao et al. Nanoscale Research Letters 2013 8:276 doi:10.1186/1556-276X-8-276