Rapid Microwave Annealing for Improved Crystallinity and Morphology of Perovskite Materials

Perovskite solar cells are gaining significant attention for their remarkable power conversion efficiency, cost-effective processing, and material abundance. This study investigates the impact of rapid microwave annealing on the crystallinity and morphology of MAPbI3 films on FTO glass substrates. Multifaceted characterization techniques, including field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), UV-Vis spectroscopy, photothermal deflection spectroscopy (PDS), and steady-state photoluminescence (PL) measurements are used to compare microwave-annealed samples with traditional hotplate-annealed samples. Microwave annealing yields significantly larger crystals in shorter processing times, suggesting enhanced crystallinity, as evidenced by SEM analysis and XRD data. UV-Vis and PDS measurements indicate improved optical properties and reduced sub-bandgap states, while PL results suggest diminished nonradiative recombination in microwave-annealed samples. However, a partial film detachment has been observed at higher microwave powers, a phenomenon explained by COMSOL simulations. These findings demonstrate rapid microwave annealing as an energy-efficient and cost-effective alternative while highlighting the need for further optimization to address film degradation issues, which remain a significant challenge. This research supports the potential for scalable, high-quality perovskite material production, facilitating large-scale production and commercialization of next-generation solar cells. Rapid microwave annealing improves perovskite film quality by enhancing grain morphology and crystallinity compared to traditional hotplate annealing at a shorter processing time. With enhanced optoelectronic properties, the films produced using this method exhibit larger grain sizes and excellentperformance. Microwave annealing. with further optimization via experiments and simulations, offers a promising and scalable method for producing high-quality perovskite materials. image (c) 2024 WILEY-VCH GmbH