Method for synthesizing high-quality colloidal cadmium-free quantum dots

Disclosed is a method for synthesizing high-quality cadmium-free quantum dots. Dissolving a copper source, an indium source and a sulfur source in liquid paraffin and heating to 100-150°C to obtain a copper indium precursor liquid; applying a vacuum and repeatedly introducing nitrogen; in an atmospheric environment or under the protection of an inert atmosphere, continuing to heat to 180-260°C then maintaining heat to obtain a core quantum dot solution; dissolving a zinc source in liquid paraffin and heating to 100-200°C to obtain a zinc precursor liquid; at that temperature, injecting the zinc precursor liquid into the core quantum dot solution; raising the temperature to 180-260°C then maintaining heat to obtain a core-shell structure quantum dot solution; purifying the core-shell structure quantum dot solution to obtain finished core-shell structure quantum dots. The present invention uses low-cost, non-toxic and chemically stable liquid paraffin as a non-coordinating solvent to manufacture cadmium-free quantum dots. Because of liquid paraffin's stable chemical properties and high effectiveness as a barrier against atmospheric moisture and oxygen, this manufacturing process can be performed in an air environment, greatly reducing vacuum environment costs.