This Materials World Network project will investigate the design rules and compatibility of n-type fullerene molecules with photoactive polymers, and apply the obtained understanding to achieve breakthrough performance in photovoltaic devices. The centerpiece of the technical approach is the rational design and synthesis of novel fullerene materials to address three key issues: a) raising LUMO Energy level of fullerene for higher photo-voltage; b) polarity fine-tuning of the fullerene by introducing substitutes to achieve optimized morphology; and c) absorption enhancement through introducing chromophores to the fullerene compounds. The relationship between the structures of these novel acceptors and the energy levels, charge generation/recombination, absorption, solubility, electron mobility, surface energy, and morphology of the donor/acceptor blend films will be comprehensively investigated. This project will be in collaboration with Prof. Kung-Hwa Wei of NCTU in Taiwan. The combined study will lead to understanding on the design rules of n-type fullerenes with emphasis on not just the LUMO-HOMO position, but also the relation between morphology, charge carrier lifetime, and charge transport in the materials system. This understanding is important for achieving organic photovoltaic performance milestones.
NON-TECHNICAL SUMMARY: Organic photovoltaics (OPVs) are an area of growing importance in exploring sustainable energy sources. This Materials World Network project seeks to provide a deep understanding of the core issues in OPV materials for energy device technology through a complementary international collaboration. This project will provide a platform for undergraduate training and showcase the importance of renewable energy to society. The project will provide education and awareness to K-12 students on clean-energy issues, science and careers in association with the outreach programs in UCLA's NSF Clean-Green IGERT program. A summer camp opportunity for high and middle school students will be provided as part of the project. In addition, a course on renewable energy and solar cells, as well as an OPV solar cell teaching module for UCLA Clean & Green IGERT are planned.
This project is supported by the Polymers Program and the Office of Special Programs in the Division of Materials Research.
