Understanding and Achieving High Performance Organic Based Photovoltaic Devices

Photovoltaic materials to be earth abundant, non-toxic and low cost to address the terawatt energy challenge. Solution processed solar cell based on organic polymer is a promising candidate due to the low material cost, low temperature fabrication and its compatibility with printing/coating processes (roll-to-roll), high material utilization etc. It also provides attractive properties like flexibility, light weight, and transparency. Bulk heterojunction (BHJ) polymer solar cell has progressed significantly in the past decade. This talk will discuss the progress in solution processed polymer solar cell in the three areas:

a) Morphology control and understanding – the formation of optimized polymer /fullerene BHJ morphology is strongly related to film formation, charge generation and recombination processes. The study of structure (morphology) – property (device) relationships in a few important polymer systems using various tools (e.g. AFM, TEM, GIXRD) will be presented.

b) Organic semiconductor / electrode interfaces – The interfaces are critical for efficient charge carrier extraction in polymer solar cell. The work on solution processed metal oxides as electron and hole buffer interface layers will be presented.

c) Device architecture investigation for high performance OPV – The innovation and study of polymer solar cells with inverted architecture, as well as inverted tandem polymer solar cell with record 10+% efficiency will be presented.

Moreover, the work on polymer solar cell also enabled us to achieve high efficiency organometal halide perovskite solar cell, as well as organic/inorganic hybrid tandem solar cells.

Biography

Gang Li is an Associate Research Professor in the Department of Materials Science and Engineering at the University of California, Los Angeles. He received his PhD in Condensed Matter Physics and MS in Electrical Engineering from Iowa State University in 2003. His postdoc research in UCLA (2004-2007) under Prof. Yang Yang was on polymer solar cell and polymer LED. Prior to joining UCLA as research faculty member in 2011, he was VP of Engineering in Solarmer Energy Inc. leading the OPV research. He has ~ 80 publications on peer-reviewed journals (Nature Materials, Nature Photonics, Science etc.), and several book chapters. Dr. Li is a Thomson Reuter Highly Cited Researcher (Materials Science, 2014) and has an h-index of 49.