2020 年 4 巻 p. 24-28
Luminescent and mono-dispersed quantum dots have been expected for the industrial applications as a useful visible- light emission source. Particularly, carbon quantum dot (CQD), composed of organic or inorganic carbon sources, has attracted much attention from the viewpoint of environmental adaptability. However, unlike existing metal/semiconductor quantum dots, CQD still has critical tasks; low quantum yields at 570−750 nm and uncertainty of microwave superiority on CQD synthesis. In this research, we attained high quantum yields (61.1 % at 580 nm) CQD using microwave solvothermal heating under low pressure. Moreover, the obvious differences in quantum yields and morphology were observed between microwave and conventional solvothermal heating conditions, as the polymerization degree/amount of polyethylene glycol was changed. We assume that this apparent difference comes from selectively heated CQD or their intermediates enhanced by microwave solvothermal heating, causing uniform pyrolysis of CQD.