Quantum Dots Synthesis // 量子點合成、尺寸-形狀控制及應用

Synthesis of Quantum Dots (QDs) (螢光量子點合成)
－傳統量子點、非鎘量子點及低鎘量子點

Quantum dots are prepared by either wet chemical or dry process. The study was started in an initiative program in Industrial Technology Research Institute of Taiwan in the end of 2000 and then became a subproject in the National Program on Nano Technology in the following year. Most of the synthetic methods for II-VI and metal nanoparticles were developed during that period of time. 

　

Precise Control of Size/Size Distribution (量子點精確尺寸控制)
－精確控制發光顏色與顏色純度(尖峰半高寬<25nm)

We have developed new approaches to synthesize quantum dots with a nearly monosized distribution. Now using non-aqueous thermal decomposition, which is one of the best ways to produce quantum dots, the size deviation of  QDs sample normally ranges between 10-30%. However, for 3 nm CdSe QDs sample, the size variation in sample for largest and smallest QDs are 3.6 and 2.4 nm respectively and their emitting colour can shift from green to orange. We have developed a novel approach to prepare a QD sample with size deviation less than ± 5%. This is based on the discontinuous growth of QDs, which was observed and published in 2009. We have also first utilized this new concept to directly multimodal size distribution QDs.

Shape-control Techniques (奈米晶形狀控制技術)

We have developed synthetic approaches to synthesize quantum dots with various structure.

Synthesis of Blue Ultra-small QDs (超小 、藍光量子點之合成)

We have developed a novel synthetic method to prepare ultra-small QDs with size around 1 nm.

　

Photoluminescence // 量子點發光性質研究

Photoluminescence mechanism from QDs with functional groups, for example, water-soluble polymer-overcoated QDs are being investigated.

QDs-based Biological Applications // 量子點生物感測器研究

Water-soluble fluorescent QDs with bio-functional groups are being developed to bio-indicators for bio-medical applications.

QDs-based White LEDs // 量子點發光二極體研究

Quantum Dots White LEDs (高演色性量子點白光光源)

High efficient fluorescent QDs have been developed to high-CRI white LEDs and backlight. The advantages of the QD white LEDs are flexible emission wavelength, high emission efficiency and a simple manufacturing process. Our lab is one of the earliest investigators in the world.

ZnSe-based White LEDs (超寬光譜量子點白光二極體)

ZnSe is a wide bandgap and blue-emitting material. We have made them emit ultra broad wide band by controlling their morphology/shape. This kind of white LED needs only single phosphor and has been shown high colour rendering index.

Direct Synthesis of High CRI Quantum Dots without Post mixing
(高演色性白光量子點單批次合成)

On the application of lighting or backlight, normally, two or three QD phosphors are mixed and the ratio is routinely tuned until a desired colour axis or CRI is obtained. However, this process is time-consuming and reduce emission efficiency as unpackaged QDs are exposed to the air for sometime. We have developed a new synthetic approach, in which CRI, emission wavelength and colour space can be directly tuned during the QD synthesis.

Multifunctional QDs // 多官能性量子點

We are advancing multi-functional QDs and devices by surface functionalization and connection to specific molecules. The purpose of this study is to develop to self-powered QDs which possess specific functions.