Electrical conductivity and electrical stability of Bi/Mg modified NiO ceramics for NTC thermistors

Thermistors with negative temperature coefficient (NTC) of resistivity are important components for sensors and actuators. High material constant (B value) NTC thermistor, i.e. high-temperature sensitivity, is one key focuses. Herein, Bi/Mg modified NiO based ceramics thermistors were prepared by conventional solid-state reaction method. Introduction Bi2O3 significantly enhances the sintering ability reduces from 1380 to 1250?C. Mg-doping (i.e. preparation Ni1-xMgxO ceramics, where x=0, 0.02, 0.05, 0.07 0.1) has significant effect on room (?25). Phase composition, microstructure, electrical property stability investigated. All have phase rock-salt structure show typical characteristics B values higher than 5300K. The an optimized resistance-change rate 1.02%after being aged at 150?C 500 h achieved. properties analysed combining X-ray photoelectron spectra complex impedance spectra.