The outdoor lifetime and performance of organic photovoltaics (OPVs) using boron subphthalocyanine (BsubPc) derivatives as electron-accepting materials is presented. The protocols followed are based on the most advanced level of outdoor testing established by the International Summit on OPV Stability (ISOS). The stability of each BsubPc is compared using three different sets of encapsulated planar heterojunction OPVs, with each set containing a different BsubPc as the electron-accepting layer. The performance and stability of each set is tested outdoors using an epoxy glue and a glass coverslip as protection from the ambient environment. Outdoor testing continued until the OPVs reached 80 or 50% of their original power conversion efficiency, as determined by frequent indoor characterization. OPVs utilizing chloro-BsubPc are shown to exhibit the highest stability and performance, while the stability of the other two BsubPc derivatives is reduced presumably as a result of their phenoxy or phenyl functionalization in the molecular axial positions. The established structure–property relationship and guidance for the design of future compounds for application in planar heterojunction OPVs are contrary to, and could not have been anticipated from, time zero laboratory testing.

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Five different solution-processed, organic photovoltaic (OPV) device architectures were screened with boron subphthalocyanine (BsubPc) as the electron acceptor paired with the PBTZT-stat-BDTT-8 polymer electron donor. These architectures include two bulk heterojunction (BHJ) devices with charge extracted in opposite directions (inverted and standard stack), a standard stack BHJ with vacuum-deposited layer on top, and two sequentially deposited planar heterojunction (PHJ) architectures. The solution–vacuum PHJ takes advantage of the ability to both solution and vacuum deposit BsubPcs with BsubPc as the acceptor layer vacuum-deposited on top of a solution-processed PBTZT-stat-BDTT-8 polymer layer. The solution–solution-mixed PHJ/BHJ represents the first example of BsubPc in a sequentially solution-deposited OPV. This architecture resulted in the best performing OPVs with a combination of high current extraction and fill factor with overall efficiency closely matching the fullerene acceptor baseline. Thus, BsubPcs in this type of architecture provides a compelling argument for BsubPcs as a replacement for fullerene-based acceptors as they are sustainable and a scalable set of chemicals. This processing method is an essential step toward large scale printing of OPVs.