High-resolution analysis of perovskite absorbers in photovoltaics

This work gives insights about the crystal formation and spatial heterogeneities on different length scales in halide hybrid organic-inorganic halide perovskite materials used for photovoltaic application. Overall, the findings supported the targeted optimization of halide perovskite solar cells. In an in-situ study of the perovskite crystal formation, the photovoltaic performance along with optoelectronic properties are monitored in real time, identifying hitherto unknown stages in the crystallization process. Solution-processed perovskite solar cells are prone to lateral inhomogeneities with detrimental influence on the device performance. Spatially resolved characterization techniques based on photoluminescence spectroscopy, light beam-induced current and thermography are employed to analyze non-uniform optoelectronic properties and quantify local loss mechanisms. A subcell-selective analysis of monolithic two-terminal silicon perovskite tandem solar cells is presented, accessing the individual subcells by multi-wavelength photoluminescence spectroscopy.