title: Synthesis, characterization and electrochemical properties of iron-zirconia solid solution nanoparticles prepared using a sol-gel technique.
abstract: The range of compositions and temperatures at which single-phase tetragonal and monoclinic Fe-containing zirconia nanoparticles are stable is reported. Both types of iron-doped zirconia particles were synthesized by annealing dried gels FexZr1-xO2, with nominal compositions in the range 0 ≤ x ≤ 0.15, over the range of temperatures between 400 °C and 1300 °C. Monophasic crystalline specimens of Fe-ZrO2 solid solutions were characterized by different techniques including X-ray powder diffraction (XRD), infrared and Raman spectroscopies (IR and Raman), and transmission electron microscopy (TEM). Energy gaps were estimated from diffuse reflectance ultraviolet-visible spectra (DRUV-Vis) and compared with those obtained from electrochemical data. Upon increasing the amount of iron in both types of iron-containing zirconia-based structures the energy gaps slightly lowered. The electrochemical properties of those solid solutions obtained using the voltammetry of microparticles (VPM) technique indicated the presence of a small portion of iron as Fe(2+) in both types of crystalline Fe-doped ZrO2. Electrochemical data suggest that the monoclinic solid solutions provide a particularly high accessibility for promoting catalytic processes such as electrochemical oxygen reduction.
authors.affiliation: Department of Inorganic Chemistry, C/Doctor Moliner 50, 46100 Burjasot, Valencia, Spain. javier.alarcon@uv.es.
authors.forename: G
authors.initials: G
authors.lastname: Herrera
authors.forename: N
authors.initials: N
authors.lastname: Montoya
authors.forename: A
authors.initials: A
authors.lastname: Doménech-Carbó
authors.forename: J
authors.initials: J
authors.lastname: Alarcón