Quantifying Performance of Permeation Barrier—Encapsulation Systems for Flexible and Glass-Based Electronics and Their Application to Perovskite Solar Cells

Effective barrier/encapsulation systems represent key enabling technologies for large-area electronics for attaining long lifetimes. Here, we unraveled architectures, application processes and water vapor transmission rates (WVTR) of transparent flexible ultra-high permeation barrier films (UHPBF) and compared them with polyethylene-terephthalate (PET), and glass barriers via calcium tests. We quantified how strongly the performance of barrier/sealant system depends on barrier orientation, adhesion, manipulation, defects and storage. We found that introducing an additional adhesion-promoting layer on the standard UHPBF stack reduced the WVTR by a factor of 5 compared to barriers without it. Finally, barriers were used for the encapsulation of perovskite solar cells (PSCs) enabling us to extract a relationship between WVTRs of the barrier/sealant systems and degradation rates (DR) of PSCs. The PSC encapsulated with UHPBFs retained 77% of initial efficiency after 840 hours, 14% lower than PSC encapsulated with glass. The DR fell exponentially when the WVTR decreased from 101 to 10-4 g m-2 d-1. Outside that range any gains or losses are mitigated by the tailing of the sigmoid curve relating the two parameters. Our results highlight important factors which will help those developing encapsulation barrier and sealant systems strategies