Cadmium sulfide quantum dots stabilized by aromatic amino acids for visible light-induced photocatalytic degradation of organic dyes

Abstract

In the present study, three aromatic amino acids including histidine, phenylalanine, and tryptophan were used as stabilizing agents for the preparation of cadmium sulfide quantum dots through a facile one-pot method under mild conditions. The as-prepared cadmium sulfide quantum dots exhibited strong visible light absorption and green photoluminescence. In addition, by using quantum dots as catalysts, rhodamine B and methylene blue could be photocatalytically degraded through the mediation of the photo-generated hydroxyl radicals under visible light irradiation. Furthermore, the photocatalytic performance of the quantum dots did not exhibit a significant decrease after five cycles of photocatalytic reaction. These results suggested that the cadmium sulfide quantum dots prepared in this study might be used as potential photocatalysts to efficiently treat organic pollutants under visible light irradiation.