20 10 The project of new polymer photoelectric functional materials and light-emitting devices presided over by Professor Cao Yong won the second prize of National Natural Science. 1) structure of trans-polyacetylene prepared by rare earth catalyst Makromol. Chemistry. , fast communication. 3 (10) (1982) 687-92 Cao, Yong; Money, Ren Yuan; Wang Fosong; Zhao and Xiao Jing
2) Spectral and electrical characterization of some aniline oligomers and polyaniline composites. Met it. ,16 (3) (1986) 305-15 Cao Yong; Li Suzhen; Xue Zhijian; Ding Guo
3) soluble polyaniline plum; Cao, Yong; Xue, Zhijian synthesis. Met it. , 20(2)( 1987) 14 1-9
4) Counter-ion induced processability of conductive polyaniline and conductive polyaniline blend in bulk polymer; Smith, Paul; Allen J. Sinser. Met it. , 48( 1)( 1992)9 1-7
5) Flexible light emitting diodes made of soluble conductive polymers; Gustafson; Cao; General Motors Treacy; Clavette, female; Colaneri, North Carolina; Nature (London), 357(6378)( 1992)477-9.
6) Improving the quantum efficiency of semiconductor polymer electroluminescence. Cao, I.D. Parker, Yu, Zhang and A.J. Haig, Nature (London), 397 (6718) (1999) 414.
7) Efficient electrophosphorescent devices based on conjugated polymers doped with iridium complexes, Mo, Yuan Min, Yang Wei, 2002, 80, 2045
8) Efficient and environment-friendly electroluminescent polymer with stable high work function metal as cathode: conjugated polyfluorene polyelectrolyte emitting green light and yellow light and its neutral precursor, Hou Lintao, Shen Huilin, Yang Wei, Cao Yong. Chemistry. Socialist 2004, 126, 9845
9) Effective electron injection of double-layer cathode composed of aluminum and alcohol-water soluble conjugated polymer; Huang, female; Mo, Yu Qing; Yang; Wang; Peng; Cao, male. 2004, 16 (20): 1826
10) Polymer light-emitting diodes, Zeng, Zeng, Peng Junbiao and Wei Yanghe printed with conductive silver paste. , 19(2007)8 10
1 1) Efficient white light emission of single copolymer: blue, green and red fluorescent chromophores on the main chain of conjugated polymer * * Luo Jie, Hou Qiong, Peng Junbiao, Wei Yang and advanced materials. , 19(2007) 1 1 13
12) A high-performance polymer heterojunction solar cell derived from polyfluorene Wang Ergang,,, Lan, Luo Chan,, Zhuang, Peng Junbiao, and *
13) High triplet energy poly (9,90-bis (2- ethylhexyl)-3,6-fluorene) as the main body of blue and green phosphorescent complexes Wu Zhonglian, Zou Jianhua, Chen Qiliang, Wei Yang, Peng Junbiao and. 20(2008)2359
14) high-efficiency single-active layer electrophosphorescent white polymer light-emitting diode, Zou Jianhua,,, Aleksandr Mikhaylov, Guillermo C. Bazin *, Wei Yang and Cao Yong * Adv. Mater. 20(2008)696 1) Machinable forms of conductive polyaniline, Y. Cao, P. Smith and A.J. Heeger, U.S. Pat. No.5,232,631(1993).
2) transparent conductor with optical quality, electroactive polymer composition P.Smith, A. J. Heeger, Y. Cao, U.S. Pat. No.59684 16 (1999).
3) electroactive polymer composition and its application in high efficiency and low working voltage polymer light emitting diode with air stable cathode, Cao Yong U.S. Pat. No.6,284,435 (2001).
4) Ultra-thin alkaline earth metal as stable electron injection cathode of polymer light emitting diode, Cao Yong U.S. Pat. No.6,452,218 (2002).
5) Thin metal oxide layer as stable electron injection electrode of light emitting diode, Cao Yong U.S. Pat. No.6,563,262.
6) U.S. Pat. No.6,866,946 (1), a high-resistance polyaniline for efficient pixelated polymer electronic displays, cooperated with Mr. Wang Fosong from Changchun Institute of Chemical Technology, China Academy of Sciences, and successfully synthesized polyacetylene with rare earth catalyst (and Mr. Shen Zhiquan also did the same work in Zhejiang University). This work not only realized the synthesis of polyacetylene catalyzed by rare earth for the first time in the world, but also obtained a variety of polyacetylenes with new structural and morphological characteristics, which marked the beginning of the research field of conductive polymers in China. In addition, in cooperation with other comrades, the doping mechanism of conductive polymers such as polyacetylene was deeply studied by various means.
(2) The oligomer of aniline and thiophene after separation and purification was used for the first time in the world, and the relationship between its structure and properties was studied. By comparing the results with the conductive polymers with the same structure, we can draw a clear conclusion about the relationship between the structure and properties of highly conductive polymers (all conductive polymers were insoluble after doping at that time). The electronic spectrum, infrared spectrum, nuclear magnetic resonance properties of aniline and doped aniline oligomer and their correlation with conductivity were studied comprehensively. This research result has been adopted by many laboratories. At present, thiophene oligomer has developed into an important high mobility device material.
(3) In cooperation with Professor Gao from the State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, the research field of organic and polymer ferromagnets has been developed in China. Compared with traditional inorganic ferromagnetic materials, organic ferromagnetic materials are light in specific gravity and easy to process, and have great economic and application prospects.
(4) With the support of the Commission of Science, Technology and Industry for National Defense, firstly, the microwave absorption characteristics of conductive polyaniline were studied, and a number of conductive polyaniline systems with excellent microwave absorption characteristics were found, and the relationship between their structures and microwave absorption characteristics was deeply studied. At that time (before 1988), this characteristic of conductive polyaniline was found in international and domestic scientific and patent documents.
None of them have been reported. This research achievement won the national invention patent 1 item and the third prize of scientific and technological progress of China Academy of Sciences.
(5) Since 1976, when high conductivity was discovered by doping polyacetylene, the research of conductive polymers developed rapidly in theory and experiment. However, there is always a problem. All conductive polymers have high conductivity after doping, but at the same time they lose their processability and become insoluble materials. The possibility of its application is greatly reduced. Starting from 1985, during my work in the Institute of Chemistry, I took exploring the solution to this problem as one of my main research directions and made some useful explorations. With the support and cooperation of a famous physicist, Professor A.J.Heeger, winner of the Nobel Prize in Chemistry in 2000, and Professor P. Smith, a polymer physicist, a new concept of counter-ion induced processability was put forward for the first time, and highly conductive polyaniline was processed into highly conductive materials (films, fibers, etc. ) Experiment from nonpolar organic solvent or general high cubic melt. At the same time, it is found that the interaction between anions, solvents and polyaniline backbone can change the chain structure and conformation of polyaniline backbone, so that the conductivity of polyaniline treated by this method is more than one order of magnitude higher than that of polyaniline obtained by general methods. In this way, the original dream of developing conductive polymers-developing conductive polymers with high conductivity and processability at the same time was realized for the first time. We also found that the unique interaction between anions and solvents (or melts) and polyaniline skeleton led to a series of new phenomena and characteristics. For example, the conductivity of polyaniline can be changed by 6-7 orders of magnitude only by changing the solvent (or anion), so that the conductivity of the material can be adjusted in a large range according to the application needs; The liquid crystal behavior of conductive polymer concentrated solution and the conductive behavior of liquid metal were observed for the first time. The mixed system of polyaniline and common polymer with conductivity threshold as low as 0. 1% was obtained. These new phenomena and features have wide practical value and important scientific significance. This research achievement has been transferred to NESTE Company for commercial production, and its products may be widely used in antistatic materials, electromagnetic wave shielding, transparent electrodes of photoelectric devices and so on. At the same time, this new concept and method have been imitated by many conductive polymer researchers and extended to other conductive polymers such as polypyrrole, which has become an important research direction of conductive polymers in recent years.
(6) Since 1994, the research focus has shifted to the research of polymer luminescent materials and devices, and a series of breakthroughs have been made in this field. In cooperation with physics researchers, soluble and highly conductive polyaniline was successfully coated on PET film to replace ITO as transparent electrode, and a flexible large-area plastic light-emitting diode was realized for the first time in the world. This paper was published in the journal Nature. By studying the interface characteristics between luminescent polymer materials and metal electrodes, the long-term working stability of the device meets the practical requirements (continuous working for more than 20,000 hours at the initial light intensity 100 CD/m2). A new method is proposed, in which stable metal such as aluminum is used as cathode, and its electroluminescent efficiency reaches or even exceeds the quantum efficiency of low work function metal such as calcium as cathode. A new understanding of the correlation between electroluminescence and fluorescence efficiency is put forward. According to the accepted traditional concept, the quantum efficiency of electroluminescence cannot exceed 25% of its optical fluorescence efficiency. Our rigorous experiments show that it is possible to break through this theoretical limit by changing the scattering cross sections of triplet and singlet States. This result shows that it is possible to obtain much higher electroluminescent quantum efficiency in polymer light-emitting devices than at present, which has important scientific and practical significance. After this research achievement was published in Nature, it was recognized by the main scholars in this field. See Bredas et al., Phys. Rev. Letter, 84 (2000) 13 1, R. Friend et al., NATURE, 404(2000)48 1 and Z.V.var
(7) 1999 After returning to South China University of Technology, the Institute of Polymer Optoelectronic Materials and Devices was established. Up to now, an advanced laboratory for material synthesis and device preparation and characterization has been built, including polymer material synthesis and device physics. Instruments and equipment are mainly imported, reaching the international level. This laboratory has been recognized as a part of Guangdong Key Laboratory of Polymer Materials. At present, the main research projects undertaken are: National Natural Science Foundation's major sub-project 1, Ministry of Science and Technology's "973" preliminary basic project 1, Guangdong Province's major innovation project 1, 2 general funds, and Guangzhou Nano Special Project 1. In addition, he also undertook the National Tenth Five-Year Plan "863" high-definition flat panel display major project, and as one of the chief scientists presided over the "973" major basic project of organic/polymer electroluminescent materials, and is making every effort to promote the development of organic/polymer luminescent materials and devices and strive to shorten the distance between China and the world. Great progress has been made in polymer light emitting devices, polymer heterojunction photovoltaic cells and conductive polymer field emission cathodes. In recent years, a number of efficient polymer luminescent materials with three primary colors of red, green and blue have been synthesized in polymer luminescent materials and devices. The external quantum efficiency of electroluminescence (EL) of red material reaches 2.5%, while that of green material exceeds 5%, and some indexes are close to the highest level reported internationally. The device has obtained 7×40 dot matrix monochrome character display screen and 96×64 monochrome image cell phone dot matrix display screen.
Among polymer photovoltaic cells, heterojunction photovoltaic cells formed of nanoparticles of derivatives of MEHPPV and C60 have been developed, and methods of forming large-area devices by screen printing have been studied. At present, the heterojunction photovoltaic cell of polymer has reached 3% in AM 1.5 solar simulation lamp (78.2 MW per square centimeter).
It is found that field emission devices with ultra-low emission threshold can be obtained by using conductive polymer nanostructures as emission cathodes. This technology is expected to develop into a new display device with ultra-low working voltage. This work has applied for the invention patent of China (application of conductive polymer and its * * * mixture on field emission cathode, application number107634.8 (20010313)).
As the chief scientist of the "973" Project, Academician Cao Yong felt a great responsibility. In order to do a good job in China and catch up with the advanced level in the world, Academician Cao often forgets his work and devotes himself to scientific research. As a scientist, Academician Cao Yong believes that scientific research achievements should be first published in academic journals and tested and recognized by peers, rather than through media hype. The value of scientists lies in making substantial contributions to the progress of science and the development of national economy with their own scientific research achievements.