Research progress of large-area organic solar cells

In recent years, organic solar cells (OSCs) have been developed rapidly, and their power conversion efficiencies (PCEs) of small-area OSCs have exceeded 19%. However, the performance of large-area devices lags far behind the development of the small-area ones. In-depth research on the major challenges of large-area organic photovoltaic devices and the development of large-area printing technologies is of great significance for promoting the industrial application of organic solar cells. Compared with small-area devices, the film thickness tolerance of the active layer, the sheet resistance of the transparent electrode, and the processing method should be mainly concentrated. Although the preparation of the large-area and stable OSCs has made significant progress and how to fabricate efficient, stable, rigid/flexible and large-area solar cells still remains a great challenge. In this review, focused on rigid and flexible substrates of large-area solar cells, we briefly summarized the new active layer materials, coating process, cathode/anode materials, electrode materials, etc. Considering the current trend, we believe the high-efficiency large-area OSCs in the laboratory would very soon lead to the production of highly efficient large-scale organic devices on an industrial scale.