Perovskite materials include a wide group of compounds whose structure in its simplest form can be represented by chemical formula ABO3. One major advantage that the perovskite structure shows is the high degree of flexibility in accommodating a wide variety of atoms in A and B sites, allowing greater control of chemical and physical properties of the material and maintaining its basic structure even at high concentrations dopants. Because of these properties, these materials have been successfully applied as capacitors, varistors, photoelectrodes, ferroelectric memories, gas sensors, etc.. Among the wide variety of materials present perovskite structure, strontium titanate (SrTiO3, ST) is one of the most materials known and studied. The possibility of creating defects in the structure of the ST compound by the insertion of dopants can lead to a significant modification of their physical properties. In this context, this thesis project aims at the synthesis and characterization of samples of composition Sr1-xAxTi1-yByO3 (A = La, B = Fe, W) in the form of thin films and thick to be applied as gas sensors . To determine the effect of doping on the properties of the material will be initially prepared samples in powder form through the polymeric precursor method and hydrothermal assisted by microwave method. Using these samples as a target, thick and thin films will be synthesized by the method of electron beam evaporation and sputerring. Optical and electrical measurements will be used to determine the effect of composition on physical properties of samples as well as its sensitivity to detect different types of gases.
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