IMPROVED LIFETIME FOR LARGE AREA INVERTED ORGANIC SOLAR CELLS, USING A NOVEL ENCAPSULATED METHOD

Abstract

In this paper, we study the performance and stability of solution-processed inverted organic solar cells based on photoactive blends composed by the conjugated regioregular poly-(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), using an active area of 2 cm². These inverted organic solar cells are fabricated with a novel top electrode design in which the silver electrode is deposited over the whole substrate to completely cover the photoactive layer, allowing an effective protection of the entire device. Consequently, initial power conversion efficiencies of 3.2% are maintained at 95% after 15h under standard illumination conditions in ambient. These IOSCs are fabricated with a novel encapsulation method in which the Ag metal top electrode was deposited over the whole ITO substrate to cover completely the photoactive layer, which allowed effective protection of the entire device. PCEs are maintained to 95% and 1 % of the initial values for the encapsulate and the un-encapsulate device respectively when exposed to air and light for15h. Conclusively, we find that the encapsulated device exhibit much higher stability than the un-encapsulated device