Solution Processed Semiconducting Polymers and Nanomaterials for Energy Harvesting

Departments: Mechanical Engineering and Materials Science
Time: Wednesday, January 25, 2017 - 2:30pm - 3:30pm
Type: Seminar Series
Presenter: Letian Dou; Department of Chemistry, University of California, Berkeley & Materials Science Division, Lawrence Berkeley National Laboratory
Room/Office: Room 107
Location:
Mason Lab
9 Hillhouse Avenue
New Haven, CT 06511
United States
See map: Google Maps

Department of Mechanical Engineering & Materials Science Seminar

Solution Processed Semiconducting Polymers and Nanomaterials for Energy Harvesting
Dr. Letian Dou
Department of Chemistry, University of California, Berkeley
Materials Science Division, Lawrence Berkeley National Laboratory

Solution-processed semiconductors show great promise in energy related applications owing to their synthetic variability, low-temperature processing, and the possibility of producing light-weight, mechanically flexible, environmental-friendly, and inexpensive electronics devices. Materials science plays a key role in connecting physics, chemistry, and engineering toward new materials with better performance. I have broad research interests in the fundamentals and applications of solution-processed organic and inorganic semiconductors for a variety of energy harvesting and electronic devices, including solar cells, photodetectors, light emitting diodes, etc.

In this talk, our rational design of low-bandgap conjugated polymers for organic photovoltaic will be discussed in the first half. By developing new organic building blocks, fine-tuning the molecular weight, solid-state packing and nano-scale thin film morphology, polymers with small optical bandgap, high charge carrier mobility, and high photovoltaic performance (with two record efficiencies) are obtained. However, the fundamental limitation of low charge carrier mobility in organic semiconductors is still there, probably due to the amorphous or semi-crystalline nature. To break the limitation, new materials with more ordered structure (higher degree of crystallinity) might be required. The other half of the presentation will be focusing on the fundamentals of crystalline polymers and inorganic perovskite nanostructures for the next generation solution-processed electronics.

Bio: Letian Dou obtained his B.S. from Peking University in 2009. He then joined Prof. Yang Yang's group in the Department of Materials Science and Engineering at UCLA, and obtained his Ph.D. in 2014 (co-advised by Prof. Fred Wudl @UCSB during 2013). His doctoral research focused on the development of conjugated polymers for organic/hybrid photovoltaic applications. His research interest also includes the synthesis, characterization, and device application of small molecules, polymer single crystals, inorganic nanostructures, hybrid materials, and related optoelectronic devices. Currently, he is a Postdoc Fellow working with Prof. Peidong Yang at the University of California-Berkeley and Lawrence Berkeley National Laboratory. He has published 32 papers with more than 7000 citations. He is recipient of the MRS student awards (2014) and the Link Foundation Energy Fellowship (2013-2015).

Host: Udo Schwarz
Wednesday, January 25, 2017
Mason Lab 107 2:30pm - 3:30pm
Refreshments 2:15pm