Themed issue on “organic optoelectronic materials”

Organic optoelectronic materials with special functionalities stem from our increasing ability to manipulate and tune the properties of organic and polymeric materials. This was achieved through the systematic variation of their molecular components, to allow for molecular-level control of the solid-state structure via arrangement of the functional molecular components into a defined architecture. Since the discovery of highly conducting polyacetylene by Alan J. Heeger, Alan G. MacDiarmid and Hideki Shirakawa in 1977, organic materials have attracted much attention as potential candidates for next generation optoelectronics, i.e., organic optoelectronics. For example, organic light-emitting diodes (OLEDs) made it possible for the development of a superior flat-panel display technology. This display technology is now commercialized for cellular phone applications and will soon be implemented in large-area high-definition television screens. Organic solar cells (OSCs) have reached quantum efficiencies over 9%, which make them attractive for delivering cheap solar power. Organic field-effect transistors (OFETs) have resulted in a revolution in developing fast and inexpensive integrated circuits on plastic substrates based on organic semiconductor elements. When combined with the advantage of solution processability, organic materials allow for the use of a variety of printing techniques, such as inkjet printing and stamping, to fabricate large area devices at low cost. Moreover, the mechanical properties of organic semiconductors also allow for flexible electronics. Certainly, the most distinguishing feature of organic semiconductors is their chemical versatility, which permits the incorporation of functionalities by molecular design, e.g., to encode factors which help to direct the properties. Actually, as an exciting research field with many potential practical applications, organic optoelectronics is progressing extremely rapidly. For example, using “organic electronics or photonics”, “organic light-emitting diode (OLED)”, “organic field-effect transistor (OFET)” and “organic solar cell (OSC)” as the query keywords to search the Web of Science, it is possible to show the distributions of papers over recent years, as shown in Fig. 1. It is very clear that the number of papers concerning organic optoelectronics has increased quickly since 2005, particularly for the study of OSCs due to the application of them in renewable green energy strategy.

Fig. 1 The distributions of published papers by year using “organic electronics or photonics”, “OLED”, “OFET” and “OSC” as query keywords to search the Web of Science.

The aim of this current themed issue focuses on novel organic and polymer materials with high electroluminescent efficiency for OLEDs, with high quantum efficiency for OSCs, with high mobility for OFETs, and so on. As a highly interdisciplinary science, the research and development of organic optoelectronic materials continually derives ideas, methods, and technologies from other research fields. Therefore, knowledge and techniques derived from chemistry, physics, materials science, semiconductors, electronics, nanotechnology and biology have been adopted in the design and development of organic optoelectronic materials.

Last but not least, this themed issue of Journal of Materials Chemistry is dedicated to one of the pioneers of the field, Professor Daoben Zhu, on the occasion of his 70th birthday. Professor Zhu is a Professor of the Institute of Chemistry, Chinese Academy of Sciences (ICCAS). He was born in 1942 in Shanghai, China. He finished high school in Shanghai and then graduated in 1968 from East China University of Science and Technology with his Bachelor’s and Master’s degrees. In the same year he joined the Institute of Chemistry, Chinese Academy of Sciences. As a visiting scientist, he performed research with Professor Heinz Staab in Max-Planck Institute for Medical Research in Heidelberg during 1977–1979 and 1985–1986. Professor Zhu pioneered his study in organic crystals with high conductivity in 1970s with Professor Renyuan Qian. Since the 1990s, he has been focusing on fullerene chemistry, molecular materials and devices. He served as vice-director (1988–1992), director (1992–2000) of ICCAS and vice-president of National Natural Science Foundation of China (2000–2008), and was selected as an academician of CAS in 1997. Prof. Zhu's current research interests focus on molecular materials and devices. His creativity and unconditional love for science have great impact beyond his over 800 published papers, and a tremendous influence on his former students, post-docs, collaborators, colleagues and friends, many of whom are leading the research of organic optoelectronics. The breadth of this impact is also evident from the diversity of the 25 papers contributed to this issue by them, which cover various areas of organic optoelectronics. Their contribution to this issue is an acknowledgement of Professor Zhu's pioneering role as a scientist in this field.

Happy Birthday, Daoben, and many more to come!

Wenping Hu

Zhenan Bao

Klaus Muellen

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