Invited Paper TF-TuA1
Perovskite Solar Cells: Material Synthesis, Device Operation and Charge Carrier Dynamics

Tuesday, November 8, 2016, 2:20 pm, Room 105A

Organic-inorganic hybrid halide perovskites have rapidly become a focal point of the photovoltaic (PV) community as a promising next-generation PV technology. Various perovskite absorbers (e.g., CH₃NH₃PbI₃ and HC(NH₂)₂PbI₃) and device architectures (e.g., mesoporous, planar, and mesoporous-planar hybrid cell configurations) have been examined with promising results by using either solution processing or thermal evaporation. The certified efficiency of a single-junction perovskite solar cell (PSC) has reached 22% after only a few years of active research. In addition to solar cell application, the fascinating optical and electronic properties of these perovskite systems have enabled their usage for various electronic devices including light emitting diodes, photodetectors, and transistors. Despite this remarkable progress associated with perovskites, there are still many fundamental questions to be addressed at both material and device levels. Further improvements are required to advance our understanding on the material effects on the fundamental physical and chemical processes that are important to device operations. In this presentation, I will present our recent studies toward a better understanding and control of perovskite nucleation, grain growth, and microstructure evolution using solution processing. The precursor chemistry and growth conditions are found to affect significantly the structural and electro-optical properties of perovskite thin films. Devices based on different grain sizes and film thicknesses were investigated to correlate the grain sizes with device performance. The impact of grain size on charge carrier dynamics was also studied. Tuning tolerance factor through solid state alloying is shown as an effective way for stabilizing perovskite structures. In addition, I will discuss briefly the role of grain boundary on charge carrier dynamics and device characteristics. These results and others will be discussed.