Abstract: The invention relates to a coating which has been applied to a substrate, comprising at least a first film and a second film which have been applied on top of each other and each comprise a transparent conducting oxide and an electron donor, wherein the second film comprises relatively at least 10 percent less electron donor than the first film. The invention also relates to a solar cell comprising a coating according to the invention. The invention further relates to a method for applying the coating according to the invention to a substrate, wherein at least a first and a second mixture which each comprise one or more precursors for a transparent conducting oxide and an electron donor are applied to the substrate, wherein the second mixture is composed such that relatively at least 10 percent less electron donor is incorporated in the film compared with the film deposited by the first mixture.

Abstract: The invention relates to a polymer optoelectronic device comprising at least a transparent conductive oxide layer, an active polymer layer, a back electrode layer and a substrate layer, wherein the transparent conductive oxide (TCO) layer has a controlled surface structure which is characterized by having an X-value in the range of from 10 nm to 500 nm, and a Y-value in the range of from 15 nm to 1000 nm, wherein the ratio between the X-value and the Y-value (X/Y) is at most 1, whereby the X-value is defined as the average value of the height of the peaks on the surface, the Y-value is defined as the average peak to peak distance on the surface, and both the X and Y values are measured by means of SEM (Scanning Electron Microscopy) or Atomic Force Microscopy (AFM).

Abstract: The invention relates to a coating which has been applied to a substrate, comprising at least a first film and a second film which have been applied on top of each other and each comprise a transparent conducting oxide and an electron donor, wherein the second film comprises relatively at least 10 percent less electron donor than the first film. The invention also relates to a solar cell comprising a coating according to the invention. The invention further relates to a method for applying the coating according to the invention to a substrate, wherein at least a first and a second mixture which each comprise one or more precursors for a transparent conducting oxide and an electron donor are applied to the substrate, wherein the second mixture is composed such that relatively at least 10 percent less electron donor is incorporated in the film compared with the film deposited by the first mixture.