Investigation of electrical properties and PTCR effect in double-donor doping BaTiO 3 lead-free ceramics

Abstract Utilizing the conventional approach, the positive temperature coefficient of resistivity (PTCR) performance of lead-free ceramics based on (1 − x %)(Ba 1− y Y y )(Ti 1.011− z Nb 0.001 Mn z )O 3 − x %(Bi 0.5 Na 0.5 )TiO 3 (BBNT x ) was examined. The BBNT x ceramics were prepared using the double donor dopant under firing at 1,350°C for 120 min in the air. The findings exhibited that when the Y 3+ concentration elevates, the room-temperature resistivity of 99%(Ba 1− y Y y )(Ti 1.011− z Nb 0.001 Mn z )O 3 – 1%(Bi 0.5 Na 0.5 )TiO 3 (BBNT1) samples initially falls and subsequently elevates. Moreover, the critical content of the samples is 0.15 mol%. Furthermore, the samples’ resistance jumping ratio can be effectively improved by adding Mn 2+ . The manganese dioxide level of 0.05 mol% yields the greatest resistance-jumping ratio. Besides, the impact of (Bi 0.5 Na 0.5 )TiO 3 (BNT) concentration on ceramics’ Curie temperature was examined in the work. Therefore, good free-lead PTCR thermistors were successfully prepared by doping 3% BNT, with a resistance jump of 4.1 magnitude.