Enhanced photoluminescence of corrugated Al2O3 film assisted by colloidal CdSe quantum dots

InGaN blue resonant cavity micro-LED with RGY quantum dot layer for broad gamut, efficient displays

The technology of RGBY micro resonant cavity light emitting diodes (micro-RCLEDs) based on quantum dots (QDs) is considered one of the most promising approaches for full-color displays. In this work, we propose a novel structure combining a high color conversion efficiency (CCE) QD photoresist (QDPR) color conversion layer (CCL) with blue light micro RCLEDs, incorporating an ultra-thin yellow color filter. The additional TiO2 particles inside the QDPR CCL can scatter light and disperse QDs, thus reducing the self-aggregation phenomenon and enhancing the eventual illumination uniformity. Considering the blue light leakage, the influences of adding different color filters are investigated by illumination design software. Finally, the introduction of low-temperature atomic layer deposition (ALD) passivation protection technology at the top of the CCL can enhance the device's reliability. The introduction of RGBY four-color subpixels provides a viable path for developing low-energy consumption, high uniformity, and efficient color conversion displays.

Spectral-temporal luminescence properties of Colloidal CdSe/ZnS Quantum Dots in relevant polymer matrices for integration in low turn-on voltage AC-driven LEDs

This work employs spectral and spectral-temporal Photoluminescence (PL) spectroscopy techniques to study the radiative mechanisms in colloidal CdSe/ZnS Quantum Dot (QD) thin films without and with 1% PMMA polymer matrix embedding (QD_PMMA). The observed bimodal transient-spectral PL distributions reveal bandgap transitions and radiative recombinations after interdot electron transfer. The PMMA polymer embedding protects the QDs during the plasma-sputtering of inorganic layers electroluminescent (EL) devices, with minimal impact on the charge transfer properties. Further, a novel TiO₂-based, all-electron bandgap, AC-driven QLED architecture is fabricated, yielding a surprisingly low turn-on voltage, with PL-identical and narrow-band EL emission. The symmetric TiO₂ bilayer architecture is a promising test platform for alternative optical active materials.

Enhanced and broadened fluorescence of ZnSe quantum dots enabled by the fluorescence energy transfer system of ZnSe quantum dots and gold nanoparticles

The enhanced and broadened fluorescence of ZnSe quantum dots (QDs) were studied by using a fluorescence energy transfer system (FETS) of ZnSe QDs and gold nanoparticles (NPs). The FETS were prepared via uniformly dispersing the gold nanoparticles into ZnSe QD solution in the condition of magnetic stirring. Enhanced and broadened fluorescence was observed on the film of the FETS due to the transfer of photo-generated carriers between the ZnSe QDs and the gold NPs, instead of the surface plasma resonance effect. The excitonic and enhanced fluorescence on the FETS film depended on the competition of electron-hole recombination and electron transfer from the ZnSe QDs to the gold NPs. In addition, because of the excitonic fluorescence of the ZnSe QDs absorbed by the gold NPs, the electrons of the s-p band of the gold NPs were further increased to facilitate its energy level shift toward the conduction band of the ZnSe QDs in order to create a blueshift in the enhanced fluorescence. This enhanced and broadened fluorescence method can be applied for controlling fluorescence in photoelectric detection, photodiodes, lightshows, and sensor devices.