Fig. 5

a Photographs of CD’s stained fingermarks on different substrate (glass, plastics, tinfoil, and weighing paper) under UV light. b The corresponding magnified pictures of above CD’s stained fingermarks. c Schematic illustration for the synthesis CD’s and photographs of the CD’s under daylight and UV light (Wang et al. 2018a, b, c) (Dyes and Pigment, 2018, 245-251, with permission from Elsevier)