Open Access Senior Thesis
Bachelor of Arts
2020 Katheryn R Kornegay
Perovskite solar cells and organic photovoltaics are both attractive because of their potential flexibility, tunable material properties, and low cost. Though perovskite solar cells have reached efficiencies comparable to conventional silicon solar cells, these have only occurred with lab-scale devices. Organic photovoltaics have much lower operating efficiencies than both perovskite and silicon solar cells, often due to non-uniformities and defects. In this thesis, we use two different techniques to better characterize these two types of solar cells. For perovskite solar cells, we use a drift-diffusion model, to characterize the transition between different doped states in its hole-transport layer, Spiro-OMeTAD, and investigate the effect on its mobility and charge-carrier density. We then compare results found from using the drift-diffusion model with other simple models. For organic photovoltaics, we use high spatially resolved thermoreflectance imaging to examine electrical shunts and other defects in PCBM-based devices under electrical. We find unexplained whole-cell heating with voltage biasing. Using our techniques used in this thesis, combined with results from other conventional techniques, will allow us to better understand, characterize and ultimately further improve the performance of all solar cells.
Kornegay, Katheryn R., "Characterizing Solar Cells" (2020). Pomona Senior Theses. 226.