UNIVERSITY OF CALIFORNIA LOS ANGELES LOS ANGELES United States
This is a collaborative research project between Prof. Yang Yang of UCLA and Prof. Kung-Hwa Wei of National Chiao-Tung University in Taiwan on high performance organic photovoltaics. During the three years, they explored several approaches involving advanced ternary blend systems as the active layer, high efficiency charge transport layers and fundamental analysis on polymerfullerene systems. They significantly improved the OPV efficiency via three different approaches a synthesizing new semiconducting small molecule acceptors and polymer donors in ternary blend systems, b employing the new ternary structure and c designing new interconnecting layers in tandem OPVs. In addition, the fundamental physics of polymerfullerene blends was studied to develop and realize strategies to achieve high efficiency devices. As a result, the group achieved tandem devices boasting in excess of 13-14 PCEs by using PBDTTBO as shown in part. The certification of high efficiency devices are under processing by National renewable energy laboratory NREL.