Toward\nCommercial-Scale Perovskite Solar Cells: The\nRole of ALD-SnO<sub>2</sub> Buffer Layers in Performance and Stability

Hybrid\norganic–inorganic perovskite solar cells (PSCs) have\nshown significant potential in photovoltaic applications due to their\nsuperior optoelectronic properties. However, the conventional electron\ntransport layer (ETL) of C<sub>60</sub> in PSCs poses challenges such\nas incomplete coverage and metal diffusion, leading to reduced performance\nand stability. This work explores the efficacy of atomic layer deposition\n(ALD) of SnO<sub>2</sub> as an interlayer between C<sub>60</sub> and\nelectrode to enhance the performance and stability of devices. Devices\nwith varying SnO<sub>2</sub> thicknesses were fabricated, revealing\nthat a 15 nm ALD-SnO<sub>2</sub> layer optimally improved the power\nconversion efficiency (PCE) to 23.85%, compared to the 22.86% achieved\nwith a BCP layer. Moreover, the SnO<sub>2</sub>-based devices exhibited\nsuperior open-circuit voltage (<i>V</i><sub>OC</sub>), short-circuit\ncurrent density (<i>J</i><sub>SC</sub>), and fill factor\n(FF). Modules (30 × 30 cm) with ALD-SnO<sub>2</sub> demonstrated\nnotable enhancements in efficiency and uniformity, suggesting the\npotential for scalable commercial applications. Photoluminescence\n(PL) and electrochemical impedance spectroscopy (EIS) analyses confirmed\nthe improved charge extraction and reduced recombination with the\nSnO<sub>2</sub> buffer layer. This research indicates that ALD-SnO<sub>2</sub> is a promising interlayer candidate for PSCs, providing a\npathway toward higher efficiency and stability in perovskite solar\ntechnology.