A novel material system is investigated in more detail in the present research in the context of an application in hybrid solar cells. Additives and a compositional gradient within the active layer are implemented in order to improve the efficiency of the hybrid solar cells. Furthermore, the solar cell performance is optimized in view of the active layer thickness and the timing of certain preparation steps. Most importantly however, it is tried to further understand the processes that occur during the spray deposition of the active layer. To this extent, a solution containing the materials of the active layer, TiO2 and P3P6T, is sprayed on glass substrates with a hole blocking layer on top, which is equivalent to the solar cell fabrication process. This is done in-situ while performing X-ray scattering measurements in grazing incidence geometry. Thereby the evolution of the morphology and crystallinity of the applied materials is investigated for different spray protocols and a vertical concentration gradient in the active layer. ukryj opis