Impact of Space Like Temperature Conditions on Metal Halide Perovskite Solar Cells

Perovskite solar cells offer significant potential as a power source in space due to their exceptional properties. Their high absorbance in the visible spectrum allows the active layer thickness to be reduced to just a few hundred nanometers. Combined with efficiencies comparable to state-of-the-art silicon devices, this results in an outstanding power-to-weight ratio. Additionally, their solution processability significantly reduces both launch and manufacturing costs, making them an attractive, cost-effective alternative to current multi-junction gallium arsenide cells. However, numerous challenges must be addressed to make perovskite solar cells viable in the harsh space conditions, including high vacuum, extreme temperatures, and radiation. Our study focuses on the extreme temperature fluctuations experienced in low Earth orbit, between the illuminated and eclipse phases, and their impact on solar cell performance. Operando grazing-incidence wide-angle X-ray scattering (GIWAXS) allows for insights into the crystal structure of perovskite active layers while the solar cell is simultaneously illuminated and subjected to extreme temperature changes. Synchrotron radiation sources, with their high beam intensities, provide the necessary high time resolution for these observations. The experiments aim to understand the complex system of the entire solar cell assembly, which consists of multiple layers and interfaces with varying thicknesses, elastic moduli, and thermal expansion coefficients. Additionally, I-V curve measurements and optical absorption spectrum tracing of the perovskite solar cells provide further information on their electrical and optical properties. This comprehensive investigation of the mechanical, optical, and electrical properties of the solar cell under extreme temperature changes from -100°C to +100°C achieves a thorough understanding of the interplay within the device. This understanding is crucial for the targeted optimization of the devices for the harsh space environment. The results of the experiments show a significant dependence of temperature on device efficiency. Additionally, the degradation of the cells is not primarily driven by the active layer but is dependent on other layers in the device and their interfaces. Based on these results, our research aims to enhance the durability and performance of perovskite solar cells in harsh space conditions, ultimately making them a more viable option for space applications.