报告人：Sai-Wing (Stephen) Tsang 博士
Department of Physics and Materials Science
City University of Hong Kong, Hong Kong SAR, China
题目：Unlocking the Dielectric Loss in Excitonic Solar Cells
地点：909号楼一楼B会议室(Conference Room B, 909-1F)
For organic solar cells (OSCs), the dielectric effect on output electrons’ maximum electric potentials (or open-circuit voltages) has long been debating, but lack of experimental evidence. By combing several techniques, the correlation between the open-circuit-voltage loss and permittivity of the materials is demonstrated for the first time. The results suggest that, in terms maximizing the output electrons’ electric potentials, OSCs can perform as efficient as their inorganic counterparts, such as silicon, but only require half as large as their permittivity, which means the photo-voltage loss due to the dielectric effect becomes negligible when the relative permittivity reaches 5. This brings insight into the further material development for high efficiency OSCs.
1. S. Chen, S.-W. Tsang, T.-H Lai, J. R. Reynolds, F. So, Adv. Mater., 2014 (in press)
2. S.-W. Tsang, S. Chen, and F. So, Adv. Mater., Vol. 25, 2434, 2013.
Dr Stephen Sai-Wing Tsang is an assistant professor in the Department of Physics and Materials Science at the City University of Hong Kong. Dr Tsang received his PhD in 2009 in the Materials Science and Engineering Department at the University of Toronto, Canada. His PhD was focused on developing experimental approaches and models to investigate the charge carrier transport across organic heterojunction, under the supervision of Prof. Zheng-Hong Lu. After his PhD, he joined the National Research Council (NRC) Canada as an Assistant Research Officer to develop solution processed quantum dots for photovoltaic applications. At 2011, he joined Prof. Franky So’s group at the University of Florida as a Postdoc Fellow to develop high efficiency polymer solar cells and investigate the corresponding device physics. Before joining CityU, he joined the Nano and Advanced Materials Institute (NAMI) in Hong Kong as an Assistant Technical Manager in the Energy division to develop CIGS and a-Si photovoltaic cells.
Dr Tsang has published over 40 peer-review papers in prestigious journals including Nature Photonics, Adv. Mater., Adv. Energy Mater., Adv. Funct. Mater., Phys. Rev. B, and Appl. Phys. Lett. etc.