Correlative imaging of optoelectronic properties for perovskite solar cells via hyperspectral luminescence imaging

Stable, high-quality, repeatable perovskite solar cells (PSCs) are crucial for commercialization, necessitating a technique providing spatially and spectrally resolved material insights for defect identification. Such a tool supports the creation of reliable processes essential for both research and development and industry. We report a multifunctional imaging approach to extract spatially and spectrally resolved information of various key optoelectronic parameters of PSCs and their correlations. The spatially resolved optical parameters include optical band gap, spectrally resolved absorptivity and luminescence, and Urbach energy of PSCs. The optical band-gap image and the spectrally resolved absorptivity of PSCs are obtained from the hyperspectral cube of luminescence measured by a hyperspectral imaging tool. Meanwhile, the spatially resolved electrical parameters including implied open-circuit voltage, ideality factor, and activation energy of recombination can be obtained by employing an illumination-intensity-dependent and temperature-dependent photoluminescence method. Based on these images, correlations between key optoelectronic parameters can be examined for different regions across the PSCs, before and after degradation tests.