Investigation of the properties of niobium pentoxide for use in dye-sensitized solar cells

This work demonstrates the obtention of Nb2O5 nanoparticles by the microwave-assisted hydrothermal synthesis method in a fast way and with the use of low temperatures. The heat treatment applied on the samples promotes the phase change in Nb2O5 from pseudohexagonal to orthorhombic as the temperature increases, with a particle size between 7.3 and 32.6nm. The band gap of the samples decreases with increasing temperature, obtaining a minimum value of 3.04 eV at 800 degrees C. Dye-sensitized solar cells (DSSC) were assembled using the Doctor Blade coating technique. The photovoltaic parameters of open-circuit voltage (Voc) and short-circuit current density (Jsc) were evaluated. The cells showed a photovoltaic response, demonstrating that Nb2O5 has a semiconductive potential. The DSSC have different characteristics regarding Jsc and Voc, showing that according to the temperature increase in the semiconductor sample, there is a decrease in the photovoltaic parameters of the cells.