The project will be a continuation of research carried out in the previous period, dedicated to the possibility of adjusting the properties of thin films for use in photosensitive devices, by modifying their structure and composition. Nano-structures and nanocomposites that have a special shape, such as nanotubes, nano-rods and very thin layers, will be investigated. For additional adjustment of the properties, the chemical composition and surface structure of the films will be modified by electrochemical etching, coating with nanoparticles and treatment in reactive gases. Support for experimental work in achieving target properties for photovoltaic, sensor and photocatalytic applications will be theoretical predictions based on DFT calculations of the electronic structure of individual materials and nanocomposites. Experiments on ZnO and TiO2, carried out in the previous project, will be extended to oxide materials that have a perovskite structure, starting with BaTiO2 and Mn-based perovskites. In further steps, the functionality of the investigated thin films will be investigated by integrating them into two-layer and multilayer structures relevant for a particular type of photosensitive devices. Various physical and chemical methods will be used for the preparation and modification of thin films. Structural and functional properties will be determined by standard techniques and correlated with formation parameters, which will allow better insight into processes relevant to thin film growth. The obtained experimental data, combined with theoretical predictions based on DFT calculations, will result in a better understanding of the influence of composition and nanostructure on macroscopic properties. This will make it possible to assess to what extent it is possible, with the procedures used in the project, to improve the properties of photovoltaics, photocatalysts and sensors. The obtained results will be published in journals with a high resonance factor in the field of materials science. The project will be partially dedicated to the education of graduate and doctoral students, which also implies the development of new careers.