title: Diffractive nanostructures for enhanced light-harvesting in organic photovoltaic devices.
abstract: We present in-coupling gratings for improving the performance of thin film organic solar cells. The impact of the grating on the absorption in the active layer is modeled and explained using a standard cell architecture. An increase in absorption of 14.8% is predicted and is shown to be independent from the active material. The structure is then applied on blade-coated devices and yields an efficiency improvement of 12%. The angular behavior of the structures is measured showing superior performance for two dimensional gratings. By simulating the current generation for different angles and illumination conditions, we predict a total yearly increase of the generated current of 12% using an optimized grating. The fabrication of these structures, moreover, is compatible with roll-to-roll production techniques, thus making them an optimal solution for printed photovoltaics.
authors.forename: Jan
authors.initials: J
authors.lastname: Mayer
authors.forename: Benjamin
authors.initials: B
authors.lastname: Gallinet
authors.forename: Ton
authors.initials: T
authors.lastname: Offermans
authors.forename: Rolando
authors.initials: R
authors.lastname: Ferrini