Inorganic Artificial Phase CdSe/ZnS QDs Serve as the Host Material for White Emission Quasi-2D Perovskite Light Emitting Devices

Quasi-2D perovskite light-emitting devices (PeLEDs) show great potential for the next generation of displays due to the surprising improvement of external quantum efficiency (EQE). However, the development of white emission Quasi-2D PeLEDs is frustrating. One obstacle is inefficient energy transfer among different electroluminescence (EL) emissive phases of the Quasi-2D perovskite layer. Here, a new strategy is proposed to resolve this problem, which is inducing an external artificial phase as the host material and building a new energy transfer path between the artificial phase and the EL emissive phases of the Quasi-2D perovskite layer. Blue CdSe/ZnS quantum dots (QDs) are an ideal choice since the size of CdSe/ZnS QDs is similar to that of perovskite grains in Quasi-2D PeLEDs and has good operational stability. The fabricated PeLEDs show a voltage-stable 1931 Commission Internationale de L'Eclairage (CIE) coordinate located at the white emission area (0.33,0.33). The highest luminescence is 365.32 cd m(-2). The fabricated PeLEDs can maintain the 95% EQE for >500 s, which is ten times higher than pure Quasi-2D PeLEDs. This work is the first to propose that inorganic QDs can serve as the host material for Quasi-2D PeLEDs, which offers a powerful tool for researchers to boost the efficiency and stability performance of white emission Quasi-2D PeLEDs.

Automated summary

Quasi-2D perovskite light-emitting devices (PeLEDs) have shown great potential for future displays, but the development of white emission PeLEDs has been challenging. However, a new strategy using blue CdSe/ZnS quantum dots (QDs) as the host material has been proposed to improve the energy transfer efficiency in the PeLEDs. The fabricated PeLEDs exhibited stable voltage, high luminance, and improved efficiency compared to pure Quasi-2D PeLEDs.