From solution to device: processing approaches to boost the photovoltaic performance of organic solar cells

• Author / Creator

  Velazquez Osorio, Adrian

• The world’s growing energy consumption and increasingly visible effects of climate change originated in continued dependence on fossil fuels has strengthened the push to develop cleaner and renewable sources of energy. Solar photovoltaic cells are at the forefront of an ongoing energy transition and a new generation of solar technology based on organic semiconductor materials – organic solar cells – is capturing the attention of researchers because of their unique properties.
  Organic solar cells are photovoltaic devices that convert radiation into electricity using carbon-abundant materials. They can be manufactured to be flexible, semi-transparent, lightweight, and inexpensively produced on a large scale by roll-to-roll processes.
  
  In this thesis work, a brief introduction on possible applications and operating principles of organic solar cells provides the background to the area. Chapter 1 describes the heart of the organic solar cell, the photoactive layer known as the bulk heterojunction, and the basics of the mechanisms behind photon harvesting via exciton generation, dissociation, and collection. The main photovoltaic metrics used to characterize these devices are also discussed.
  Chapter 2 provides an overview of approaches used in the design of donor and acceptor materials and mentions how computer-driven optimization is emerging as an experimental paradigm to navigate the vast variable space involved in making the bulk heterojunction. The core section of this chapter focuses on approaches to improve solution processability of PM6:BTP-BO-4Cl OPV cells. Special emphasis is given to the application of methanol-based solvent annealing treatments and their role in inducing film dewetting of the PEDOT:PSS layer.
  Chapter 3 continues this focus on optimization of the bulk heterojunction by discussing the application of microwave annealing of a ZR1:BTP-BO-4Cl composition. A brief critical overview on the application of microwave annealing to increase photovoltaic performance of organic solar cells is presented. Later, evaluation of different microwave annealing setups is examined.

• Subjects / Keywords

  • OPV
  • microwave annealing
  • methanol effect
  • bulk heterojunction

• Graduation date

  Spring 2022

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-7p60-ht07

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.