National Taiwan University, Taiwan
Title: Environmentally affordable fluorescent nanotechnology for efficient lighting
Biography: Ching-Fuh Lin
A novel nanotechnology for environmentally benign as well as efficient white light generation is developed. Compared to conventional phosphors that overly rely on rare-earth elements (REEs), this proposed nanotechnology is REE free and is instead based on the integration of II-VI semiconductor nanoparticles and polymeric materials. ZnO and ZnS:Mn nanoparticles are combined with poly (9,9-di-n-hexylfluorenyl-2,7-diyl) to create efficient warm-light-emissive nanocomposites. The resultant nanocomposites encompass three different photon-generating routes, which can lead to blue, green and orange emissions, respectively. White light thus can be directly generated from the nanocomposites as pumping by commercial UV- or blue-LED. Moreover, a wide tunability of color temperatures ranging from below 3000K to 6000K, which embraces both candle light and white light, is achievable by the nanocomposite. A warm-white light emission with above 90% high quantum efficiency has also been demonstrated under the commercial UV-LED excitation. Additionally, we successfully explore an innovative technique to synthesize II-VI-based nanoparticles without quantum-confinement effect. The prepared nanoparticles can exhibit a strong absorption at 453 nm, which well fits the wavelength of commercial blue-LEDs (450-460 nm), and efficiently convert blue light to brightly orange light. The proposed nanoparticle-based technology can serve as a promising solution not only to the health issues involved in current blue-LED-YAG lighting systems, but also to the eco-friendly affordable efficient-lighting technology.