Crina Suciu

Modified Sol-gel Method used for Obtaining SOFC Electrolyte Materials

A new modified sol-gel method using sucrose and pectin as organic precursors was used to obtain 7ScSZ and 11ScSZ nanoparticles as electrolyte materials for solid oxide fuel cells (SOFCs). Scandia stabilized zirconia (ScSZ) offers significantly higher conductivity than most other electrolyte materials (e.g. yttria stabilized zirconia, YSZ). The high cost of scandia can be compensated to some degree by the use of thin electrolyte films. Also, it is important to reduce the costs incurred by all the intermediate fabrication steps of SOFCs. The new organic precursors used in the modified sol-gel method have the advantages of being ubiquitous, cheap, easy to handle and store, and environmentally friendly. The produced nano-powders were pressed to pellets and sintered in two different ways to obtain different grain sizes. The powders and pellets were investigated using TEM (Transmission Electron Microscopy), XRD (X-ray Diffraction), physical adsorption (BET), and EIS (Electrochemical Impedance Spectroscopy) to determine the morphology, particle size, crystal structure, crystallite size and specific surface area of the powders and the electrical properties of the sintered pellets.