News and Events


Seminar - Improvements in Perovskite solar cells by Prof. Wallace Woon-Fong LEUNG
日期:2018 年 10 月 25 日 ( 星期四)
Time:10:30 am – 11:30 am


Perovskite solar cells (PSC) is perhaps one of the hottest topic in photovoltaics in the past decade. The energy efficiency of the laboratory unit reaches 23.2% as compared to 14% that was attained in 2013 by Prof. Michael Gratzel’s group in EPFL, Switzerland.

The perovskite crystal is excellent in harvesting energy across the entire visible spectrum up to 800 nm, however, as with other solar cells one of the several key weakness is the electron-hole recombination due to crystal imperfection and excess grain-to-grain boundaries and the lack of effective transport mechanism to transport the photo-generated electrons. In our presentations, we will discuss several ways of developing large uniform nanocrystals with reduced boundaries and traps, and the use of graphene in enhancing crystal size and quality, as well as providing dedicated pathways for charge transport. The efficiency of our PSC has reached 20%.


Prof. Wallace W-F Leung received his BS in Mechanical and Aerospace from Cornell University, and MS and ScD both in Mechanical Engineering from MIT. For the past 40 years, he has worked on filtration and separation, centrifugation, nano-energy, nano-environment and nano-health. For 25 years, he was with Bird/Baker Hughes, Schlumberger and Gulf Oil in the United States. In the past 14 years, he is Chair Professor of Innovative Products and Technologies in Mechanical Engineering of the Hong Kong Polytechnic University. He is a fellow of American Institute of Chemical Engineers, American Society of Mechanical Engineers, American Filtration and Separations Society, Hong Kong Institute of Engineers, and Hong Kong Academy of Engineering Sciences. He holds 50 US patents and two books to his credit. He is the Chair of International Delegation on Filtration with 13 member countries including US, UK, Germany, France, Scandinavia, Austria, Hungary, Japan, Australia, Taipei, China, S. Korea, and India. He is also the chair of the World Filtration Congress, San Diego, CA, USA, 2020. He has delivered numerous keynote and plenary talks around the globe on topics of his research.