Engineering of Semiconductor Energetics of Scaffolds in Perovskite Solar cells from Surface Chemical Point of View - Prof. Maetani (Qi unit)

Abstract:

The organic-inorganic hybrid perovskite solar cell is of huge interest for next generation solar cells by utilizing printable process. The interface engineering is considered as one of the key technologies for improving the cell efficiency and long-term stability of devices.  As titania is the most commonly used material for the oxide scaffold layer, our interest focuses on controlling titania surface to engineer the crystallization and electron transfer properties at scaffold/perovskite interface.  In this presentation, I especially focus on the facet chemistry of the oxide scaffold, and report a few studies of perovskite solar cell systems addressing the surface chemical functionality of exposed crystalline facet of scaffold.  In our studies, the single crystal titania with specifically exposed facet and specific facet-dominant titania nanoparticles are utilized for constructing a model system and solar cell devices, respectively.  In the model system, the affinity of perovskite film components, Pb and Cl, revealed differences depending on contacted facet of titania. In addition, the solar cell properties with specific facet dominant anatase titania meso-porous scaffold is discussed in detail with regarding the electron transport properties attributed to the energetics of conduction band and electron trap states.  Furthermore, I discuss utilization of exposed facet on scaffold to control the interfacial affinity and the energetics, which are important factor for the film formation and ultimately the device properties including the charge transport properties.  From the prospective for large-scale process, the “pin-point” microwave interfacial heating is also addressed for high through-put high quality annealing of perovskite film with good device properties.

Bio:

Dr. Masato  Maitani was born in Osaka, Japan, in 1976. He received B.E. degrees in Mechanical Engineering from Osaka City University (Osaka, Japan) in 1999 and M.E. degrees in Material Engineering from Osaka University (Osaka, Japan) in 2001.  He joined to Sharp Corporation (Osaka, Japan), and engaged in research on advanced production technology of liquid crystal display in 2001.  In 2004 he moved to the United States to join a research group as a Ph. D. candidate supervised by Professor D. L. Allara and T. S. Mayer in Pennsylvania State University (State College, PA, USA), and engaged in research on surface and interfacial chemistry with self-assembled monolayers for organic electronic devices.  He also joined Information & Quantum Systems Laboratory, Hewlett-Packard Laboratories (Palo Alto, CA, USA) as a vesting researcher supervised by R. Stern Williams in 2007, and engaged in research on organic-inorganic interfaces for plasmonic devices.  He received his Ph. D. degree in Department of Material Science and Engineering of Pennsylvania State University in 2009.  In 2010, he joined the Department of Applied Chemistry in Tokyo Institute of Technology (Tokyo Japan) as an assistant professor and then associate professor in 2014.  In 2016, he moved to the Research Center for Advanced Science in The University of Tokyo (Tokyo, Japan) as associate professor.  His current interest is focused on the interfacial chemistry of charge transfer in organic-inorganic hybrid solar cells and the interaction between electromagnetic field and materials for processing electronic materials.  He is currently also a research fellow in the Research Institute for Catalysis Science, Hokkaido University. 
Dr. Maitani currently has published more than 60 articles in addition to several book chapters and holds more than 10 JP patents with a few patent pending.  He received the young investigator award in Tokyo Inst. Tech. in 2012 and a few prizes in conferences.  He is a member of the American Chemical Society, the Japan Society of Applied Physics, the Chemical Society of Japan, the Electrochemical Society of Japan, and the Japanese Photochemistry Association.