Emerging strategies toward mechanically robust organic photovoltaics : focus on active layer

Abstract

Mechanical stability of organic photovoltaics (OPVs) is required not just for portable applications, which must accommodate strain as a function of operation, but also for manufacturing, transportation, and utility-scale applications. However, the mechanical reliability of OPVs is often disregarded compared with other stress (thermal, oxygen, moisture, irradiation). The key to improving the mechanical stability of OPVs lies in realizing mechanically robust active layers. This perspective first analyzes working scenarios of flexible OPVs (static and dynamic conditions) and strategies toward achieving mechanically robust active layers. Then, the recent achievements in improving the mechanical robustness of active layers are summarized in the aspects of all-polymer active layers, single-component active layers, and third component strategies. In the end, an outlook and perspective on the future of the field are provided to help improve the mechanical stability of active layers.