MS Defense: Liang Wang
Fabrication and Characterization of Bulk Heterojunction Organic Solar Cells
Advisor: Professor Mihri Ozkan
Abstract: The global energy demands have been dramatically increasing over the past decades, and consumption of conventional energy resources has caused a lot of environmental problems, urging the development of renewable energy supply. In this case, solar cells, converting unlimited solar power into electricity, can play a unique role to offer secure, clean, sustainable energy to support the most technologically advanced society. Nevertheless, conventional solar cells have many practical applications with initially high cost, and polymer solar cells have been the new initiative towards cost-effective solar energy harvesting for photovoltaic applications. They have shown their great potential for large-area production due to its economically viable cost, roll-to-roll processing, versatility of chemical structure and mechanical flexibility. Herein, significant efforts are underway to enhance the efficiency which is one step closer to the level of commercialization. Utilization of lead sulfide colloidal semiconducting quantum dots in polymer solar cells has extended the absorption of solar spectrum into the near infrared region, facilitating the overall power conversion efficiency. Strategies in optimization of various post-annealing conditions were also investigated to maximize photo-induced charge separation and to increase low carrier mobility towards enhanced efficiencies. Polymer fullerene solar cells with metalized DNA, a new approach with incorporation of one dimensional nanostructure, were also introduced.