Brazil’s abundant natural resources, particularly titanium dioxide (TiO \(_{2}\) ) and niobium pentoxide (Nb \(_{2}\) O \(_{5}\) ), position the country for strategic advances in optoelectronic and photovoltaic technologies, including third-generation solar cells such as dye-sensitized solar cells (DSSCs). In this study, TiO \(_{2}\) and Nb \(_{2}\) O \(_{5}\) nanoparticles were co-dispersed at different mass concentrations to fabricate Nb \(_{2}\) O \(_{5}\) –TiO \(_{2}\) single-layer photoanodes for DSSCs. The films were deposited by spin-coating and doctor-blade techniques onto microscope slides and conductive glass substrates, and characterized by mechanical profilometry, X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and two-point probe electrical measurements. Prototype DSSCs incorporating the different photoanodes were assembled and evaluated by current–voltage measurements under simulated solar illumination and dark conditions. The films are thick, rough, and porous, with phase segregation between TiO \(_{2}\) and Nb \(_{2}\) O \(_{5}\) , as well as a reduction in average crystallite size upon the addition of Nb \(_{2}\) O \(_{5}\) nanoparticles. Niobium incorporation promoted an increase in electrical conductivity and yielded DSSC prototypes with improved short-circuit current density, open-circuit voltage, and overall power conversion efficiency relative to devices based on conventional TiO \(_{2}\) photoanodes. These results indicate that niobium-containing TiO \(_{2}\) nanostructures enhance the electrical properties of the photoanode and contribute to improved device performance.
