Fig. 7: The proposed fluorescent mechanism of DHQP and CDs.

a Photo of the CDs and DHQP dissolved in EtOH, and the solutions were excited by a 532 nm laser. b The UV-vis contrast spectra of the DHQP and CDs. c and d EEM spectra of DHQP and CDs dissolved in ethanol. e and f Schematic diagram of the real experimental absorption and emission of DHQP and CDs. (ic: internal conversion, VR: vibration relaxation, ET: electron transfer)