Understanding and Designing Interfaces and Defects in Perovskite Solar Cells

Juan-Pablo Correa-Baena
School of Materials Science and Engineering, Georgia Tech

Abstract: Perovskite solar cells promise to yield efficiencies beyond 30% by further improving the quality of the materials and devices. Electronic defect passivation, and suppression of detrimental charge-carrier recombination at the different device interfaces has been used as a strategy to achieve high performance perovskite solar cells. In this presentation, I will discuss the role of electronic defects and how these can be passivated to improve charge-carrier lifetimes and to achieve high open-circuit voltages. I will discuss the characterization of 2D and 3D defects, such as grain boundaries, crystal surface defects, and precipitate formation within the films, by synchrotron-based techniques. The importance of interfaces and their contribution to detrimental recombination will also be discussed. As a result of these contributions to better understanding 2D and 3D defects, the perovskite solar cell field has been able to improve device performance. Albeit the rapid improvements in performance, there is still a need to improve these defects to push these solar cells beyond the current state-of-the-art.

Bio: : Prof. Correa-Baena joined the faculty at Georgia Tech in the Spring of 2019. Prof. Correa-Baena received his PhD from the University of Connecticut and was a postdoctoral fellow at the Ecole Polytechnique Fédérale de Lausanne and the Massachusetts Institute of Technology. His contributions have helped boost the efficiencies of perovskite solar cells beyond 25%. He has also been named 2019 Highly Cited Researcher by Clarivate Analytics (Web of Science), which makes him a top 0.1% most cited scientist across fields. The Correa-Baena group focuses on the understanding and control of low-cost semiconductor electronic dynamics at the nanoscale, particularly in solar cell and light emitting diode applications. Advanced deposition techniques are being developed in his group with emphasis on nanometer-scale design and high throughput. Current projects include high-throughput deposition of halide perovskites with nanoscale control, synchrotron-based elemental imaging and mapping techniques with nanoscale resolution, and development of new materials for improved solar cell performance.