Organic-inorganic hybrid perovskites are chemically diverse semiconductors which have led to solar cells with efficiencies > 22%. Incorporation in multijunction (tandem) configuration with established photovoltaics (Silicon, CIS) would expedite commercialization, but this effort is limited by optoelectronic quality of large-bandgap mixed halide perovskites (APbIxBr3-x; A = methylammonium, formamidinium, cesium). Efforts to make these alloys more stable have been ineffective due to inevitable compromises in efficiency. My idea is to both increase hydrophobicity and passivate defects via incorporating bulkier organic cations in APbIxBr3-x to create simultaneously stable and efficient large-bandgap absorbers. Rational development of these multidimensional (2D/3D composites) perovskites enabled by CEI funding would facilitate exploration of composite compositional space to realize material for tandem photovoltaics. With my expertise in device engineering, I will further tailor device interfaces, energetic landscape, and processing to fully tap the potential of these newly-developed absorbers in photovoltaics and ultimately realize commercially relevant high-efficiency, stable tandems.
Advisor: Alex K-Y. Jen – Materials Science & Engineering