Environmental-friendly synthesis method of fluorescent carbon dot with up-down conversion function

The invention belongs to the field of preparation of fluorescent carbon dots, and discloses a synthesis method of the fluorescent carbon dot with an up-down conversion function. The method comprises the following steps of: adding chilli flakes into water and evenly mixing, thereby obtaining a mixture; transferring the mixture into a hydrothermal kettle, performing a hydrothermal treatment at 120 to 200 DEG C for 2 to 10 hours, and cooling and filtering, thereby obtaining a brown liquid; centrifuging the brown liquid for 10 to 20 minutes, thereby obtaining a supernatant; dialyzing the supernatant by using a dialysis bag with the flow interception volume of 3500; and collecting a dialysate after dialyzing for 10 to 30 hours, thereby obtaining the fluorescent carbon dot. By taking a cheap raw material as a carbon source and the water as a solvent, the method for synthesizing the fluorescent carbon dot with the up-down conversion function in an environmental-friendly manner has the effects that the process is sim