Three- and Two-Dimensional Tin and Lead Halide Perovskite Semiconductors: Synthesis and Application in PhotovoltaicsPublic Deposited
Halide perovskites, AMX3 (A = monocation, B = Ge, Sn, or Pb, and X = halogen), present a versatile class of solution-processable semiconductors made from earth abundant materials with outstanding electrical and optical properties. Their solar cell efficiencies have dramatically increased from ~9% to ~22% in less than five years since 2012, a rate that has never been seen before in photovoltaic research. Critical to the final goal of commercializing perovskite solar cell technology is achieving device long-term stability and eliminating toxic elements in device components. This thesis uses 3D AMX3 perovskites as a stand-in to develop a new class of lead-free, moisture stable, functional and highly tunable 2D Ruddlesden–Popper (BA)2(MA)n−1SnnI3n+1 (n is an integer) perovskite semiconductors. Synthesis, thin film fabrication, extensive characterization, and solar cell device structure-performance relationships are presented throughout the entire thesis.