Zhejiang University Department of Chemistry quantum dot light-emitting diode made important progress

According to the website of the National Natural Science Foundation of China, supported by the National Natural Science Foundation of China (21233005) and other supporters, Peng Xiaogang, Department of Chemistry, Zhejiang University and Jin Yizheng, a researcher of the Department of Materials, collaborated in the field of quantum dot light-emitting diode (QLED) research Significant progress has been made. Relevant research results published in "Nature" (Nature). This paper reports a novel LED device that uses quantum dots as electroluminescent material. Its performance far exceeds that of other quantum dot LEDs reported in the literature so far, and the new device can be prepared by a simple solution processing route.

LED as the next generation of lighting and display of the core devices have been recognized by the industry. GaN epitaxial growth quantum well LED device is the popular product on the market. However, GaN epitaxial growth quantum wells require ultra-high vacuum, ultra-high purity raw materials, ultra-density power consumption and other conditions. To this end, both the display industry or the lighting industry, have chosen the blue LED and the conversion of rare earth phosphor relatively low-cost ideas. And this combination of routes led to the low quality of light, the color gamut can not fully meet the requirements and other defects. Unlike GaN quantum well LEDs, organic light-emitting diode (OLED) devices emit light at the center of organic molecules and can therefore be prepared with less demanding vacuum conditions. OLED has been applied in the small screen display. However, due to the OLED electroluminescent center for organic molecules, thermal stability and chemical stability has been a thorny issue. The direct performance of the device processing technology demanding, the device life expectancy often can not be expected and so on.

Obviously, QLED is expected to combine the advantages of both GaN quantum well LEDs and OLEDs. However, after 20 years of unrelenting efforts by scientists, the comprehensive performance of QLEDs - including efficiency, life expectancy and processing technology - is far behind people's expectations. This is mainly due to the quantum dot and QLED device compatibility and QLED special structure of two reasons. Zhejiang University team designed and synthesized a special QDED QDED quantum dots, and QLED own device characteristics were analyzed to find the key issues of this type of device structure, and then through the device to insert a layer of nano-insulating layer to solve the positive, The key difficulty of injecting charge balance. The success of these two aspects, the experimental verification of the feasibility of practical QLED. This indicates that QLED is expected to play an important role in both lighting and display industries.