Abstract: The invention concerns a photoelectric conversion device comprising: at least one photoconversion element comprising at least one organic photoconversion layer or an inorganic layer comprising quantum dots or perovskites; at least a first grating structure arranged on a first side of the photoconversion element; and at least a second grating structure arranged on a second side of the photoconversion element; wherein said at least a first grating structure is arranged so as to direct a near-infra-red light portion of light incident on said first grating structure into said photoconversion element, the said at least a second grating structure being arranged to reflect at least a part of said near-infra-red light portion back into said photoconversion element and to pass visible light out of the photoelectric conversion device.

Abstract: The disclosed invention consists of high efficiency organic solar cells (0) with a multi layer structure, consisting of cathode layer (1), organic acceptor layer (2), organic donor layer (3), conductive anode layer (4) and a substrate layer (5), where an adjustment of electronic levels of separated layers is achieved by introduction of at least one intermediate matching layer (x). In conjunction with the selection of active layer (3) consisting of cyanine dyes with appropriate counterions (e.g. hexafluorophosphate), high performance organic solar cells with long lifetimes can be fabricated with a fast and simple manufacturing method.