Abstract
Porous Ba(Ti,Sb)O3 ceramics were fabricated by adding corn-starch at 20 wt %. The effect of atmosphere on the PTCR characteristics of the porous Ba(Ti,Sb)O3 ceramics and the role of oxygen on the grain boundaries in the PTCR characteristics of the Ba(Ti,Sb)O3 ceramics were investigated. In air, O2, N2, and H2 atmospheres, the electrical resistivity of Ba(Ti,Sb)O3 ceramics below 150 °C was independent of atmosphere, while it was strongly dependent on atmosphere above 200 °C. The low electrical resistivity in reducing atmospheres was due to a decrease in potential barrier height, which originated from an increase in the number of electrons owing to the desorption of chemisorbed oxygen atoms at the grain boundaries. In a N2 atmosphere, the electrical resistivity of Ba(Ti,Sb)O3 ceramics during the cooling cycle was lower than that during the heating cycle, and then the electrical resistivity of the porous Ba(Ti,Sb)O3 ceramics during subsequent heating and cooling cycles was increased again by exposure to an O2 atmosphere.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Journal of Materials Science: Materials in Electronics
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.