Nd2O3 doped BaTiO3ceramics(the additive content was respectively 0.001, 0.002, 0.003, 0.005, 0.01 molar ratio)were prepared by Sol-Gel method to study their dielectric characteristics and electric conductivities thr...Nd2O3 doped BaTiO3ceramics(the additive content was respectively 0.001, 0.002, 0.003, 0.005, 0.01 molar ratio)were prepared by Sol-Gel method to study their dielectric characteristics and electric conductivities through X-ray photoelectron spectrum (XPS). The results showed that the dielectric characteristics of Nd2O3 doped BaTiO3 ceramics were improved by doping. When Nd2O3 content was 0.003 mol, the results were even better, the dielectric constant was increased, the dielectric loss was decreased, the Curie-temperature (Tc) was 110 ℃, and the frequency characteristic was also good. The resistivity of Nd2O3 doped BaTiO3 ceramics was lower than that of pure BaTiO3 ceramics, when Nd2O3 content was 0.001 mol,the resistivity was (2.364×)108 Ω·m, the smallest. The grain resistance of Nd2O3 doped BaTiO3 ceramics exhibited NTC effect, but the grain boundary resistance showed PTC effect, and the grain boundary resistance was larger than that of the grain resistance, so the PTC effect originated from the grain boundary. The analysis of the element binding energy through X-ray photoelectron spectrum were indicated that the quantivalence of Ba2+and Ti4+in Nd2O3 doped BaTiO3 ceramics was variable, and resulted in the improvement of the conductibility of BaTiO3 ceramics.展开更多
To reduce the coercive field of Na_(0.5)Bi_(0.5)TiO_(3),Ba TiO_(3)were added as dopant materials.Then the(1-x)Na_(0.5)Bi_(0.5)TiO_(3)-xBaTiO_(3)ceramic samples were produced in solid synthetic way.The optimum preparat...To reduce the coercive field of Na_(0.5)Bi_(0.5)TiO_(3),Ba TiO_(3)were added as dopant materials.Then the(1-x)Na_(0.5)Bi_(0.5)TiO_(3)-xBaTiO_(3)ceramic samples were produced in solid synthetic way.The optimum preparation condition and piezoelectric properties of the samples were investigated.The XRD results show that the fabric transites from rhombohedral to tetragonal gradually with the substitution of the Ba^(2+).The morphotropic phase boundaries(MPB)exists in the composition range of 0.06.展开更多
In this paper, the conductivities of BaPbO 3 and BaPbO 3-Nd 2O 3 system ceramics are studied. The experimental results show that the charge carriers in this system ceramics are donor electrons captured in oxygen v...In this paper, the conductivities of BaPbO 3 and BaPbO 3-Nd 2O 3 system ceramics are studied. The experimental results show that the charge carriers in this system ceramics are donor electrons captured in oxygen vacancies. The conductivity and the PTC characteristics of the BaPbO 3-Nd 2O 3 ceramics are obviously different from those of pure BaPbO ceramics.展开更多
正温度系数(positive temperature coefficient,PTC)热敏陶瓷是一类关键电子功能陶瓷,因其优异的特性在加热元件、传感器、电路保护器、温度控制器、电器消磁等领域都有广泛的应用。BaTiO_(3)作为主体材料制备的正温度系数热敏电阻(posi...正温度系数(positive temperature coefficient,PTC)热敏陶瓷是一类关键电子功能陶瓷,因其优异的特性在加热元件、传感器、电路保护器、温度控制器、电器消磁等领域都有广泛的应用。BaTiO_(3)作为主体材料制备的正温度系数热敏电阻(positive temperature coefficient thermistor,PTCR)是目前用量较大的一类正温度系数元件,具有重要的研究意义。本文阐述了正温度系数热敏材料的分类及其优缺点,介绍了正温度系数效应、热敏机理及BaTiO_(3)基正温度系数材料的半导化原理,综述了BaTiO_(3)基正温度系数热敏陶瓷国内外研究现状,分析了移峰剂、施主掺杂、受主掺杂、烧结工艺等因素对BaTiO_(3)基正温度系数热敏陶瓷的影响,总结了正温度系数热敏元器件的应用原理及其在相关领域的应用,并对正温度系数热敏陶瓷的无铅化进行了展望。展开更多
文摘Nd2O3 doped BaTiO3ceramics(the additive content was respectively 0.001, 0.002, 0.003, 0.005, 0.01 molar ratio)were prepared by Sol-Gel method to study their dielectric characteristics and electric conductivities through X-ray photoelectron spectrum (XPS). The results showed that the dielectric characteristics of Nd2O3 doped BaTiO3 ceramics were improved by doping. When Nd2O3 content was 0.003 mol, the results were even better, the dielectric constant was increased, the dielectric loss was decreased, the Curie-temperature (Tc) was 110 ℃, and the frequency characteristic was also good. The resistivity of Nd2O3 doped BaTiO3 ceramics was lower than that of pure BaTiO3 ceramics, when Nd2O3 content was 0.001 mol,the resistivity was (2.364×)108 Ω·m, the smallest. The grain resistance of Nd2O3 doped BaTiO3 ceramics exhibited NTC effect, but the grain boundary resistance showed PTC effect, and the grain boundary resistance was larger than that of the grain resistance, so the PTC effect originated from the grain boundary. The analysis of the element binding energy through X-ray photoelectron spectrum were indicated that the quantivalence of Ba2+and Ti4+in Nd2O3 doped BaTiO3 ceramics was variable, and resulted in the improvement of the conductibility of BaTiO3 ceramics.
基金Funded by the National Natural Science Foundation of China (No.61704113)the Shenzhen Science and Technology Program (No.GJHZ20210705141805015)the Scientific Research Project in School-level (SZIIT2019KJ026)。
文摘To reduce the coercive field of Na_(0.5)Bi_(0.5)TiO_(3),Ba TiO_(3)were added as dopant materials.Then the(1-x)Na_(0.5)Bi_(0.5)TiO_(3)-xBaTiO_(3)ceramic samples were produced in solid synthetic way.The optimum preparation condition and piezoelectric properties of the samples were investigated.The XRD results show that the fabric transites from rhombohedral to tetragonal gradually with the substitution of the Ba^(2+).The morphotropic phase boundaries(MPB)exists in the composition range of 0.06.
文摘In this paper, the conductivities of BaPbO 3 and BaPbO 3-Nd 2O 3 system ceramics are studied. The experimental results show that the charge carriers in this system ceramics are donor electrons captured in oxygen vacancies. The conductivity and the PTC characteristics of the BaPbO 3-Nd 2O 3 ceramics are obviously different from those of pure BaPbO ceramics.
文摘正温度系数(positive temperature coefficient,PTC)热敏陶瓷是一类关键电子功能陶瓷,因其优异的特性在加热元件、传感器、电路保护器、温度控制器、电器消磁等领域都有广泛的应用。BaTiO_(3)作为主体材料制备的正温度系数热敏电阻(positive temperature coefficient thermistor,PTCR)是目前用量较大的一类正温度系数元件,具有重要的研究意义。本文阐述了正温度系数热敏材料的分类及其优缺点,介绍了正温度系数效应、热敏机理及BaTiO_(3)基正温度系数材料的半导化原理,综述了BaTiO_(3)基正温度系数热敏陶瓷国内外研究现状,分析了移峰剂、施主掺杂、受主掺杂、烧结工艺等因素对BaTiO_(3)基正温度系数热敏陶瓷的影响,总结了正温度系数热敏元器件的应用原理及其在相关领域的应用,并对正温度系数热敏陶瓷的无铅化进行了展望。