Recent Advances in Buffer Layer Engineering for Performance Enhancement in Inverted Perovskite Solar Cells: Material-Based Classification

Buffer layers play a crucial role in improving the performance and stability of inverted perovskite solar cells (IPSCs) by mitigating interface defects. These layers enhance interfacial properties by passivating defects, improving wettability, preventing undesirable charge recombination, and blocking external degradation factors. This review categorizes buffer layers based on their material composition, including inorganic, organic, and hybrid materials, and discusses their respective functionalities. Additionally, the mechanisms behind their interface-enhancing effects are explored to provide insights into optimizing buffer layer design for more stable and efficient IPSCs.