Department of Electrical and Computer Engineering
Fall 2014 Seminar Series
Seminar Title: Molecular Engineering of Light Absorption Materials for Solar Energy Conversion Time: 3:00-4:00 PM, Friday, Nov 14, 2014
Location: ECE 101 Lankford Lab
Speaker:
Hongshan He Eastern Illinois University Abstract:
Solar energy is an environmentally friendly alternative energy source that can make a significant contribution to solving worldwide energy problems. Low-­‐cost and easy fabrication of dye-­‐sensitized solar cells (DSCs) and perovskite solar cells (PSCs) are promising for future indoor and outdoor applications. Though greater than 13% and 19% energy conversion efficiency has been achieved in DSCs and PSCs, low energy conversion efficiency and poor long-­‐term stability are still two major concerns in regard to its competitiveness with other types of solar cells. In this talk, several strategies will be presented to address these barriers. For DSCs, we found that inserting a thiophene or a fluorene unit between a donor and an acceptor in porphyrin structures led to the gradual broadening of the absorption spectra, resulting in increased energy conversion efficiency. However, adding a small complementary BODIPY dye in a porphyrin solution during the dye-­‐loading process may or may not benefit the energy conversion depending upon the porphyrin structures. Further studies also showed that replacement of a benzoic acid by an 8-­‐hydroxyquinoline significantly increased the binding strength of the dye molecules on titanium dioxide nanoparticles. The trade-­‐off of these strategies will also be discussed For PSCs, We found the NiO layer can enhance the charge separation efficiently. The low-­‐temperature processing method makes this type of devices promising for flexible and printable electronics. Speaker Bio:
Dr. Hongshan He is Assistant Professor of Chemistry, Eastern Illinois University. He received his Ph.D. in Chemistry from Sun Yat-­‐sen University in 1996. He then joined the faculty of National Huaqiao University in 1998, where he was promoted to full professor in 2006. Dr. He also worked in Hong Kong Baptist University as a visiting research scholar, North Dakota State University as a postdoctoral research associate, and in the College of Engineering at South Dakota State University as a research faculty. In 2013, he became a tenure-­‐tracking faculty of Eastern Illinois University. Dr. He received many awards including American Science and Engineering Education (ASEE) Summer Fellowship Award in 2012, NSF MRI grant award in 2012, Eastern Illinois University President’s Funds for Research and Creativity award in 2013, and American Chemical Society Petroleum Research Fund grant Award in 2014. He was the led organizers of two MRS symposium in 2012 and 2014. Dr. He’s research interests include photoactive materials and their applications in solar energy conversion, bioimaging, sensing as well as photocatalysis.