Toward Commercial-Scale Perovskite Solar Cells: The Role of ALD-SnO₂ Buffer Layers in Performance and Stability

Hybrid organic–inorganic perovskite solar cells (PSCs) have shown significant potential in photovoltaic applications due to their superior optoelectronic properties. However, the conventional electron transport layer (ETL) of C 60 in PSCs poses challenges such as incomplete coverage and metal diffusion, leading to reduced performance and stability. This work explores the efficacy of atomic layer deposition (ALD) of SnO 2 as an interlayer between C 60 and electrode to enhance the performance and stability of devices. Devices with varying SnO 2 thicknesses were fabricated, revealing that a 15 nm ALD-SnO 2 layer optimally improved the power conversion efficiency (PCE) to 23.85%, compared to the 22.86% achieved with a BCP layer. Moreover, the SnO 2 -based devices exhibited superior open-circuit voltage ( V OC ), short-circuit current density ( J SC ), and fill factor (FF). Modules (30 × 30 cm) with ALD-SnO 2 demonstrated notable enhancements in efficiency and uniformity, suggesting the potential for scalable commercial applications. Photoluminescence (PL) and electrochemical impedance spectroscopy (EIS) analyses confirmed the improved charge extraction and reduced recombination with the SnO 2 buffer layer. This research indicates that ALD-SnO 2 is a promising interlayer candidate for PSCs, providing a pathway toward higher efficiency and stability in perovskite solar technology.