Characteristics of a Thick Film Ethanol Gas Sensor Made of Mechanically Treated LaFeO_3 Powder

摘要

In this work, fabrication of LaFeO_3 thick film ceramics for ethanol gas sensor made of mechanically treated (milling) powder was studied. The thick films were fabricated using screen printing technique from LaFeO_3 powder treated by HEM (High Energy Milling). The films were baked at 800°C for one hour and analyzed using XRD and SEM. Sensitivity of the films was studied by measuring resistance of them at various temperatures in a chamber containing air with and without ethanol gas. Data of XRD showed that the thick film crystalizes in orthorombic structure with space group of Pn*a. SEM data showed that the films consisted of small grains with grain size of about 225 nm. According to the electrical data, the LaFeO_3 thick films that produced in this work could be applied as ethanol gas with operating temperature of about 275°C.