Materials toward the Upscaling of Perovskite Solar Cells: Progress, Challenges, and Strategies

Perovskite solar cells (PSCs) are promising candidates for the next generation of photovoltaic technologies due to their constantly improved efficiencies, which gain much attention from both the scientific and industrial communities. Although the performance of PSCs is dramatically enhanced, most certified or reported high-efficiency PSCs are still limited to a relatively small active area. The degradation of efficiency and stability accompanied by upscaling must be solved, being a bottleneck toward industrialization. This review focuses on the research progress, challenges, and strategies on large-area PSCs, especially each functional material in various device architectures, including perovskites, hole transport materials, electron transport materials, and electrodes. Finally, the main issues related to each functional layer of PSCs from laboratory to industry are presented and an outlook on the research direction of large-area PSCs is given.