Synthesis of Zn0·1Cd0·9S heterostructure with N-doped graphene quantum dots and graphene for enhancing photoelectric performance in UV–visible light

Abstract In the present study, a heterostructure based on Zn0·1Cd0·9S, N-doped graphene quantum dots (N-GQDs), and graphene was successfully prepared by a simple method. Various analyses are conducted to determine the structure, morphology, and materials performance of the synthesized composite. The results exhibit that the Zn0·1Cd0·9S/N-GQDs/graphene heterostructure presents excellent photoelectric performance with a high photocurrent of 4.43 × 10−5 A/cm2 and 3.43 × 10−5 A/cm2 under light irradiation of 365 nm and 405 nm, respectively. It demonstrates a two-fold photocurrent enhancement in comparison to blank Zn0·1Cd0.9S. This remarkable improvement is ascribed to a mechanism in which the N-GQDs act as photosensitizers, enhancing the absorption ability. Concurrently, graphene serves as a carrier mobility substrate, facilitating the separation of the photogenerated electron–hole pairs. The synergetic effect between Zn0·1Cd0·9S, the N-GQDs, and graphene enhances the photoelectric performance. The Zn0·1Cd0·9S/N-GQDs/graphene heterostructure provides a new route for the enhancement of the photoelectric performance of a semiconductor under UV–visible light.