Recent progress of hybrid cathode interface layer for organic solar cells

Organic solar cells (OSCs) have gained conspicuous progress during the past few decades due to the development of materials and upgrading of the device structure. The power conversion efficiency (PCE) of the single-junction device had surpassed 19%. The cathode interface layer (CIL), by optimizing the connection between the active layer and the cathode electrode, has become a momentous part to strengthen the performances of the OSCs. Simultaneously, CIL is also indispensable to illustrating the working mechanism of OSCs and enhancing the stability of the OSCs. In this essay, hybrid CILs in OSCs have been summarized. Firstly, the advancement and operating mechanism of OSCs, and the effects and relevant design rules of CIL are briefly concluded; secondly, the significant influence of CIL on enhancing the stability and PCE of OSCs is presented; thirdly, the characteristics of organic hybrid CIL and organic-inorganic hybrid CIL are introduced. Finally, the conclusion and outlook of CIL are summarized.