Integration of green CuInS2/ZnS quantum dots for high-efficiency light-emitting diodes and high-responsivity photodetectors

Ternary I-III-VI quantum dots (QDs) have been regarded as an alternative to Cd-and Pb-based QDs because of their appealing optoelectronic properties and their deficiency in highly toxic components. In this paper, we present the synthesis of highly luminous and emission-tunable CuInS2/ZnS core/shell QDs and their application to the fabrication of highly efficient electroluminescent QD light-emitting diodes (QLEDs). To evaluate the possibility of applying CuInS2/ZnS QDs to photodetectors (PDs), the CuInS2/ZnS-graphene hybrid PDs with a high-responsivity were successfully constructed for the first time. In this study, QLEDs based on the as-prepared CuInS2/ZnS core/shell QDs exhibited a high external quantum efficiency of 3.36% at a forward current of 2.8 V, which is higher than that of CuInS2-based electroluminescent QLEDs reported previously. The resulting PD exhibited a surprisingly high responsivity of 35 A/W. CuInS2/ZnS QDs provide new opportunities for the fabrication of non-toxic QLEDs and PDs exhibiting high performances and are promising for future applications in the field of optoelectronic devices. (c) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.