zro2气敏陶瓷掺杂优化设计zro2气敏陶瓷掺杂优化设计.doc

ZrO2 气敏陶瓷掺杂优化设计 ZrO2 气敏陶瓷掺杂优化设计山东大学毕业论文摘要本文在 ZrO2 - Y2O3 二元体系中添加第三组元,构成三元系统。相对与氧化锆二元系统,其气敏性以及导电性等一系列性能均有明显的提高, 较之氧化锆二元系统具有更强的适用性和市场竞争性。立足于氧传感器的研究,通过掺杂 1 %- 5mol % Al2O3 或 1% - 6mol % Al ,以凝胶注模方法制取坯体, 通过对成品的电性能的测试, 其比电阻随测试温度的变化是非线性的。随温度的升高氧离子的激活能降低, 因而引起跃迁几率增加, 同时还有一些本征空位也参与氧离子的传输,从而随着温度的增加使得通过 ZrO2 固体电解质中的氧离子数目增加,电阻在较低温情况下迅速下降,电导率上升。在掺杂量为 3mol% Al2O3 时, 其电导率最高, 当掺杂量高于这一数值时,其电导率下降。利用 X- Ray 衍射研究了氧化锆气敏材料的晶格常数,衍射强度等性能,对成品的性能进行解释。关键词: YSZ ;气敏陶瓷;导电性; Al2O3 1 山东大学毕业论文 Abstract: The paper is aimed adding the third element into the - Y2O3 binary paring with the binary system, the gas sensitivity and conductivity are advanced greatly, thus the application is enlarged and petition increased. The new materiAl which is based on oxide-sensor, doped with 1% - 5mol %, 1% - 6mol % Al gain s its green body by Gel- the testing of finished product,with the change of temperature the electric resistance is ing non-liner. The reason is that with the temperature increasing, the activity energy of decreases, the transition prob ability raises, at the same time, some dummy bits are engaged in the transition of oxygen ion. So with the increment of temperature, the amount of oxygen ion in ZrO2 solid electrolyte grows greatly, the electric resistance fall down at low temperature , but the electric conductivity increases. When the doping amount of Al2O3 is 3mol%, the conductivity is maximum, but the conductivity reduces with the amount ing larger. The performance such as lattice parameter and the strength of inflection of the new materiAl is tested by XRD, aiming at explaining the properties of this product. Keyword: YSZ ; gas sensitive ceramic ; conductivity ; Al2O3 2 山东大学毕业论文第一章绪论 研究背景随着各种固体电解质材料的不断研制与性能的提高, 固体电解质的种类日增多,应用领域也不断扩大。固体电解质材料有很多,如氧化锆,氧化钛等, 其对气体的敏感性也不尽相同。大多数材料只对某一种气体比较敏感, 有时当一种材料中添加一些其它的掺杂物, 却会改变其原来的性质, 而对另一种气体敏感。众多固体电解质中,研究较为成熟的 ZrO2 固体电解质, 由于具有测量精确度高、响应时间短、测量范围广、无需基准参比气体以及可直接以电压( 或电流) 形式输出等特点, 广泛用于金属熔体中的含氧量、空气分离产物中的含氧量、窑炉和烟道气中的含氧量测量,以及金属热处理炉中气氛控制、内燃机的空气燃料比控制, 以