Long term aging studies of Graphene/Surlyn encapsulated organic photovoltaic devices

Abstract

Flexible and transparent moisture barrier films have been climacteric importance for the further development of the polymer solar cells (PSCs). Herein, a monolayer graphene (2D atomic crystal) embedded in a flexible polymer (GEPs) was used to encapsulate the solar cells. The improvement of long-term stability of PSCs still needs to be overcome for their commercialization to be feasible.Degradation mechanisms studied in ITO/ZnO/PTB7:PC70 BM/MoO3/Ag inverted PSCs by Capacitance-voltage, Capacitance-frequency and light intensity dependent measurements is reported here. Measurements was performed on encapsulated and nonencapsulated (controlled and ambient environment) cells under AM1.5 illumination. However, the degradation studies performed with the ISOS D1 protocol suggested the increased lifetimes of the PSCs encapsulated with GEPs barrier films. A promising lifetime of more than 20000 hours was demonstrated with less than 22 % degradation for encapsulated devices.