Organic Polymers as Additives in Perovskite Solar Cells

The wide field of polymer chemistry has recently encountered the unique, promising field of perovskite solar cells (PSCs). Thanks to their chemical versatility, the possible applications of organic polymers within solar devices have been highly diversified as charge-transporting materials, of either hole or electrons, or as additives, being these blended into the designed layer or used as a buffer layer. The use of different organic polymers as additives has demonstrated to be beneficial for the device performance and stability, thanks to an improved morphology of the thin layers and to their assistance in the charge transport. This perspective intends to provide the reader with a clear viewpoint on the role that polymers play as additives in PSCs. Thus, the most important examples describing the use of these macromolecules as additives in each of the possible target layers within PSCs are reported. Understanding the role played by the polymer together with the necessary chemical functionalities that provide each role within the solar cells is of primary importance in the future design of polymeric materials to be used in PSCs. Therefore, with this perspective article, we expect to contribute in the rational design of next-generation organic polymers suitable to surpass the current state of the art in PSCs.