63-2:Distinguished Paper: Large-scale Luminance Enhancement Film with Quantum Rods Aligned in Polymeric Nanofibers for High Efficiency Wide Color Gamut LED Display

Inch-sized aligned polymer nanofiber films with embedded CH3NH3PbBr3 nanocrystals: electrospinning fabrication using a folded aluminum foil as the collector

Perovskite nanocrystal embedded polymer nanofibers with polarized emissions are interesting materials for down-shifting applications. By using a folded aluminum foil as a collector, we fabricated inch-size aligned polymer nanofiber films with embedded CH₃NH₃PbBr₃ nanocrystals by adapting an electrospinning technique. It was found that the addition of an appropriate amount of cyanoethyl cellulose (CEC) makes the dispersion of MAPbBr₃ in the nanofibers more uniform. Using a precursor solution with MAPbBr₃ of 10% and CEC of 1 wt%, the resulting nanofiber films show strong polarized emission with quantum yields up to 51%. The emission dichroic ratio and emission polarization ratio can reach 5.21 and 0.43, respectively. These polarized emissive films can be potentially applied as down converters for liquid crystal display backlights and other polarization selective photonic devices.

Ultrasensitive Detection of Volatile Organic Compounds by a Freestanding Aligned Ag/CdSe-CdS/PMMA Texture with Double-Side UV-Ozone Treatment

Volatile organic compounds (VOCs) are organic chemicals having a high vapor pressure at room temperature. Chronic exposure to VOC vapor can be potentially dangerous to human health. In this study, we build a high-performance freestanding aligned Ag/CdSe-CdS/poly(methyl methacrylate) (PMMA) texture to detect VOC vapors. The insight of this new VOC-sensing material is based on electrospinning techniques, ultraviolet (UV)/ozone treatments, and nano-optics. The incorporation of CdSe-CdS core-shell quantum rods (QR) and silver nanocrystals in the PMMA nanofibers amplifies the polarization response of long rods in VOC detection, thus increasing the sensitivity of VOC-sensing materials. Further, the uniaxial aligned Ag/QR/PMMA sensing material was treated by UV-ozone etching to increase surface absorption. The advanced double-sided UV-ozone etching on the uniaxial aligned Ag/QR/PMMA efficiently enhanced the extinction changes of VOCs. Two categories of solvents, typical VOCs and alcoholic VOCs, were put into practical tests for the Ag/QR/PMMA VOC-sensing materials. The Ag/QR/PMMA reached the detection limit for 100 ppm butanol within 1 min. The freestanding aligned Ag/CdSe-CdS/PMMA texture is a newly designed nanocomposite device for environmental risk monitoring. It can be accepted by the market compared to the other highly sensitive commercial VOC-sensing materials.