Improved InP/ZnSe/ZnSeS/ZnS quantum dots for single-terminal carrier-injection light-emitting devices

The wavelength tunable and environmentally friendly InP quantum dots are considered one of the most powerful alternatives to cadmium-based quantum dots, and the luminescent devices prepared with them also show great potential. There is still room for improvement in the synthesis methods and device applications of InP based quantum dots. In this work, we report one pot synthesis route for InP/ZnSe/ZnSeS/ZnS green QDs based on tris(dimethylamino)phosphine (DMP) phosphorus by using the strategy of multi shell coating and gradient heating to reduce surface defects of quantum dots. The shell structure, dosage, and growth temperature have all been taken into account in order to explore better performance of InP QDs. The synthesized green quantum dots have 86 % PLQY and a full width at half maximum of 36 nm. In addition, the synthesized green InP quantum dots are applied in AC QLED devices. The experimental results show that the luminescence intensity is affected by the driving voltage and frequency, which is similar to the working mode of non-carrier-injected emitting devices. And there is a matching value between the voltage and frequency.