Speakers

Prof. Yang YANG received his Ph.D. in Physics and Applied Physics from the University of Massachusetts. Prof. Yang has more than 500 refereed papers; more than 30 issued patents, and more than 200 plenaries, keynote, and invited talks. He has accumulated of more than 130,000 citations and his H-Index is ~171. His major research interests are in the solar energy and highly efficient electronic devices. Currently he is the Carol and Lawrence E. Tannas Jr. Endowed Chair Professor at UCLA.

Prof. Yang is a fellow of European Academy of Science, the American Association for the Advancement of Science, Materials Research Society, Royal Society of Chemistry, American Physical Society, Electromagnetic Academy, and SPIE, International Society for Optics and Photonics. Recently, he has received the following honors/awards: invited to join the Advanced Materials Hall of Fame (2021); Highly Cited Researcher in three major fields: Materials Science, Chemistry, and Physics, Thomson Reuters (now Clarivate Analytics) (Only ~20 people world-wide elected, 2017, 2018, 2019); 2019 Sustainable Energy Award by UK Royal Society of Chemistry; Highly Cited Researcher in both Materials Science and Chemistry Categories (2013-2016, & 2020).

Title Near-Infrared Materials: The Turning Point of Organic Photovoltaics 

Abstract

Abstract Near-infrared (NIR)-absorbing organic semiconductors have opened up many exciting opportunities for organic photovoltaic (OPV) research. For example, new chemistries and synthetical methodologies have been developed; especially, the breakthrough Y-series acceptors, originally invented by our group, specifically Y1, Y3, and Y6, have contributed immensely to boosting single- junction solar cell efficiency to around 19%; novel device architectures such as tandem and transparent organic photovoltaics have been realized. The concept of NIR donors/acceptors thus becomes a turning point in the OPV field. 

Here, I will report the development of NIR-absorbing materials for OPVs. According to the low-energy absorption window, here, NIR photovoltaic materials (p-type (polymers) and n-type (fullerene and nonfullerene)) are classified into four categories: 700–800 nm, 800–900 nm, 900–1000 nm, and greater than 1000 nm. Each category covers the design, synthesis, and utilization of various types of donor (D) and acceptor (A) units. 

The structure– property relationship between various kinds of D, A units and absorption window are constructed to satisfy requirements for different applications. Subsequently, a variety of applications realized by NIR materials, including transparent OPVs, tandem OPVs will be presented. Finally, challenges and future development of novel NIR materials for the next-generation organic photovoltaics and beyond will also be discussed.