The electro-electronic ceramics that crystallize in the perovskite structure have attracted the attention of the scientific community due to their properties such as high chemical stability, mechanical and electrical conductivity through oxygen vacancies, interstitial protons, electrons or holes. Furthermore ceramic matrix composites are used to anchor metal nanoparticles. In this work, lanthanum chromite samples doped with nickel and strontium ((La(1-x)Srx)a(Cr(1-y)Niy) O(3-delta),x=0,10%,20%; y=0,10%,20%; a=100%,90%,80%) will be synthesized using the Pechini method. The resins will be calcined using the optimum temperature determined by thermogravimetry. The phases present wil be determined using X-ray diffraction and quantified by the Rietveld method. The samples will be treated with hydrogen atmosphere for the formation of nickel metal nanoparticles. Magnetic measurements will be performed to observe the presence and influence of superparamagnetism from the nanoparticles enabling the theoretical calculation of particle size and comparison with size observed through transmission electron microscopy. Electric transport phenomena will be characterized by impedance spectroscopy measurements in a wide range of frequencies and temperatures using different atmospheres. We hope that these studies make a contribution to the understanding of superparamagnetism, but also to propose an alternative material for electrochemical applications.
News published in Agência FAPESP Newsletter about the scholarship: