【摘要】 采用溶胶-凝胶法制备了纯BaTiO₃、Pr,Mn液相掺杂及气相多元扩渗改性的BaTiO₃陶瓷.研究结果表明,Pr掺杂能使纯BaTiO₃陶瓷的室温电阻率下降为1.01×10⁵Ω·m;而Mn掺杂使室温电阻率升高为1.50×10¹³Ω·m.但Pr和Mn的气相扩渗都能降低BaTiO₃陶瓷的室温电阻率至1.08×10³Ω·m和1.29×10⁵Ω·m.Pr-Mn共渗BaTiO₃陶瓷出现了典型的NTC效应.XRD分析表明,Pr或Mn掺杂并不能改变BaTiO_a陶瓷的物相结构,但经Pr-Mn共渗后,出现了新化合物BaMn_0.12Al_1.88O₄和Al₈Mn₄Pr的特征峰.XPS分析表明,气相多元渗使Pr,Mn,C元素都扩渗到陶瓷体内,并使各化学元素之间的结合更加牢固.SEM测试结果表明,Pr,Mn气相扩渗使陶瓷表面明显改观,晶粒生长完整,粒度分布均匀,气孔率下降.更多还原

【Abstract】 Pure BaTiO₃ ceramics and Pr,Mn-doped BaTiO₃ ceramics were prepared by a sol-gel method.The pure BaTiO₃ ceramics were modified by the penetration of Pr and Mn in gaseous state, their structure and electrical properties were studied.The results show that the resisitivity of Pr-doped BaTiO₃ ceramics is decreased to 1.01×10⁵Ω.m,the resisitivity of Mn-doped BaTiO₃ ceramics is increased to 1.50×10¹³Ω.m,while both Pr and Mn penetration can decrease the resisitivity of BaTiO₃ ceramics evidently,which is 1.08×10³Ω.m and 1.29×10⁵Ω.m,respectively .The Pr-Mn penetrated BaTiO₃ ceramics show a distinct NTC effect.The XRD results show that the perovskite structure of Pr or Mn doped BaTiO₃ ceramics does not change obviously,but there are new peaks of BaMn_0.12Al_1.88O₄ and AlsMn₄Pr in Pr-Mn penetrated BaTiO₃ ceramics.The XPS results show that Pr,Mn and C element are penetrated into BaTiO₃ ceramics,leading to the binding energy of modified BaTiO₃ ceramics increase and their stability improve.The SEM results show that Pr and Mn penetration can improve the surface state of BaTiO₃ ceramics,the grains become finer and grow more integrally than pure BaTiO₃ ceramics, the porosity are decreased visibly.更多还原