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 C60 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 SnO2 as an interlayer between C60 and electrode to enhance the performance and stability of devices. Devices with varying SnO2 thicknesses were fabricated, revealing that a 15 nm ALD-SnO2 layer optimally improved the power conversion efficiency (PCE) to 23.85%, compared to the 22.86% achieved with a BCP layer. Moreover, the SnO2-based devices exhibited superior open-circuit voltage (VOC), short-circuit current density (JSC), and fill factor (FF). Modules (30 × 30 cm) with ALD-SnO2 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 SnO2 buffer layer. This research indicates that ALD-SnO2 is a promising interlayer candidate for PSCs, providing a pathway toward higher efficiency and stability in perovskite solar technology.