Synthesis of SrTi1-xFexO3, Zn1-xCoxO and CuAlO2 thin film oxide compostions for application as gas sensors

• Grant number: 13/12473-0
• Support Opportunities: Regular Research Grants
• Duration: July 01, 2014 - December 31, 2016
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Valmor Roberto Mastelaro
• Grantee: Valmor Roberto Mastelaro
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated grant(s): 14/50641-5 - Surface structures in doped perovskite ceramics, AP.R SPRINT

Abstract

Resistive gas sensors based on metal oxides in the form of thin or thick films are the devices most used and studied for the control of toxic and flammable gases in technological processes and open environment. Although a significant amount of work is being devoted to this field of research, efforts are being made in order to find materials that exhibit best surface and bulk properties to be used as gas sensors, allow a more selective detection and have a low production cost. In this context, this research project has as main objective the study of the deposition of metal oxide thin films obtained through the electron beam evaporation and RF sputtering techniques. Samples to be deposited belong to the SrTi1-xFexO3 , Zn1-xCoxO x= 0.1, 2.5 and 5 mol% and CuAlO2looking their application as gas sensors. To achieve this goal, we are requesting funds to purchase a system for deposition of thin films based on electron beam evaporation and RF sputtering techniques. The acquisition of this equipment will allow, in addition to conducting a systematic study of the process of deposition of SrTiO3 thin films doped with iron which has proven to be an excellent sensor ozone gas, expand our line of research to other materials already identified as good candidates for gas sensors, as ZnO doped with cobalt compound and the CuAlO2 system. Besides the use of conventional techniques for characterization, we aim to perform a structural "in-situ" analysis in the above-mentioned samples when subjected to a temperature variation and under the action of different types of gases. This study will be conducted through the technique of x-ray absorption spectroscopy and has as main objective to determine which structural and electronic parameters (local order and oxidation state) that show significant changes when the sample is subjected to the same conditions performed during electrical measurements used to analyze the sensitivity of these samples to different types of gases analyzed. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DA SILVA, LUIS F.; MASTELARO, VALMOR R.; CATTO, ARIADNE C.; ESCANHOELA, JR., CARLOS A.; BERNARDINI, SANDRINE; ZILIO, SERGIO C.; LONGO, ELSON; AGUIR, KHALIFA. Ozone and nitrogen dioxide gas sensor based on a nanostructured SrTi0.85Fe0.15O3 thin film. Journal of Alloys and Compounds, v. 638, p. 374-379, JUL 25 2015. (12/15170-6, 13/12473-0, 13/07296-2, 13/09573-3)