Electrical properties and aging characteristic of Sb/Ga co-doped single-cation oxide SnO2

A system of negative temperature coefficient (NTC) thermistors with adjustable room-temperature resistivity (rho(25)) and temperature sensitivity should have great application prospect for various requirements. Herein, Sb/Ga co-doped SnO2 ceramics with nominal formula of Sn0.95-xSb0.05GaxO2 (x = 0, 0.01, 0.02, 0.03, 0.04, and 0.05) were fabricated by conventional solid-state reaction process. The phase component, electrical conductivity, temperature sensitivity of resistivity and aging characteristic were investigated. Analysis of X-ray diffraction shows that the prepared SnO2-based ceramics consist of tetragonal phase. The ceramics exhibit typical characteristic of NTC of resistivity. With change of Ga-ion content, the ceramics possess adjustable rho(25) from 3.24 omega center dot cm to 0.54 M omega center dot cm together with related NTC material constants (B-25/85 values) from 140 to 5384 K. The analysis of complex impedance spectra reveals that both band conduction and hopping conduction are responsible for electrical properties of the prepared ceramics. The aging treatment induced at 150 degrees C revealed that all ceramics exhibit good electrical stability. The possible aging models were investigated by analysis of the change of element valences before and after aging.

Automated summary

A system of negative temperature coefficient (NTC) thermistors with adjustable room-temperature resistivity (rho(25)) and temperature sensitivity was fabricated using Sb/Ga co-doped SnO2 ceramics. The ceramics exhibited typical characteristics of NTC of resistivity and good electrical stability.