An Electrochemical Characterisation of Silica–Zirconia Oxide Nanostructured Materials for Fuel Cells

Silica–zirconia nanoparticles were successfully synthesised using the precipitation process. The surface area and shape of the Si-ZrO₂ nanoparticles were investigated using BET, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (HRTEM). The HRTEM results demonstrate that silica was successfully integrated into ZrO₂ nanoparticles with a mixture of nanorod and nanosphere shapes. The element analysis (EDX) reveals the presence of silica (14.61%) and zirconia (1.18%) nanoparticles, as well as oxygen (83.65) on the surface. The BET results demonstrate a larger surface area of 185 m²/g and pore volume (0.14 cm³/g). The XRD measurements confirmed the transition of amorphous silica into the monoclinic phase of the zirconia nanoparticles. The electrochemical characteristics of the silica–zirconia nanoparticles were tested in a potassium chloride solution. With a large specific surface area and an appropriate pore size distribution, a pair of broad and symmetric redox peaks were centred at −0.15 V and 0.6 V.