Tailoring the Transport Layer Interface for Relative Indoor and Outdoor Photovoltaic Performance

The ability to achieve notable indoor power conversion efficiency (PCE) makes organic photovoltaics (OPV) a potential technology for indoor applications. Currently, ongoing research in indoor OPVs focuses on improving both their indoor PCE and their stability. However, little attention has been given to investigating the fabrication yield of indoor OPVs, a pivotal determinant of their potential commercial viability. In this study, we discovered that despite assessing the PCE of OPVs under indoor and solar illumination conditions using the same devices, the fabrication yields under these distinct light sources vary significantly. Employing diverse analytical measurements, we elucidated the underlying mechanisms contributing to this variance. Our findings suggest that disparities in fabrication yield resulted from the interfacial interactions between the hole transport layer (HTL) and the active layer. Particularly, the interfacial behavior between these layers plays a decisive role in achieving elevated fabrication yields in indoor OPVs. Furthermore, we demonstrate the function of a combination of two HTLs (TAPC/MoO3), which not only enhances the indoor PCE of OPVs but also substantially improves the fabrication yield of indoor OPVs. Our study offers insights and critical guidance for the advancement of indoor OPVs with high fabrication yields.