基于La_(1-x)Sr_xMnO_3敏感材料的电流型NO_x传感器研究  

Research on Amperometric-type NO_x Sensor Based on La_(1-x)Sr_(x)MnO_3 Sensitive Materials

作　　者：胡明江[1] 马步伟[1] 王忠[2] 

机构地区：[1]河南城建学院能源与建筑环境工程学院,平顶山467036 [2]江苏大学汽车与交通工程学院,镇江212013

出　　处：《分析化学》2013年第10期1531-1536,共6页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(Nos.50376021;50776042);河南省高等学校青年骨干教师资助项目(No.2010GGJS-150);河南省科技厅重点攻关计划项目(No.112102210363)资助

摘　　要：采用喷雾热分解技术制备了NOx传感器敏感材料La1-xSrxMnO3以多孔的氧化钇稳定的氧化锆（YSZ）为固体电解质，设计了一种新型的电流型NOx传感器。采用X射线衍射仪、扫描电子显微镜、程序升温脱附仪和X-射线光电子能谱（XPS）仪，表征了La1-xSrxMnO3粉体的相组成和微观形貌，分析了敏感材料La1-xSrxMnO3对NOx吸附强度与Mn氧化价态变化机理。在NOx传感器气敏性能测试装置上，利用DJS-292型恒电位仪测试了传感器敏感特性、温度特性、动态响应、抗干扰和稳定性。结果表明，以La0.5Sr0.5MnO3为敏感材料的NOx传感器，在极化电压为-300mV，NOx浓度为0—1000μL／L时，NOx传感器线性度和灵敏度最大值分别为96．6％和97．1％，承受的温度上限为1200℃。在650℃，浓度从200μL／L转换到500μL／L时，NOx传感器动态响应和恢复时间分别为25s和15S。此传感器对CO、SO2、甲醛、乙醛、菲、丙酮和丙烯醛等气体具有良好的抗干扰性能。在汽车上连续使用12个月后，响应电流衰减了8．6％，响应电流正常时间为5个月。The sensitive materials La1-xSrxMnO3 of NOx sensor were prepared by the spray pyrolysis method. A new amperometric-type NOx sensor was designed with Lax-x SrxMnO3 as the sensitive electrode and yttria- stabilized zirconia （YSZ） as the solid state electrolyte. The crystalline phase and microstructure of sensitive electrode in NO~ sensor were displayed by XRD and SEM, NO adsorption intensity and Mn oxidation mechanism of sensitive electrode in NOx sensor were analyzed by temperature-programmed desorption （TPD） and XPS. These characteristic tests of NOx sensor were carried out on the traits of sensitive performance, temperature, dynamic response, interference and stability by the DJS-292 potential instrument in the sensor test bench, the conclusion demonstrated that the NOx sensor based on La0.5Sr0.5MnO3, when the polarization voltage was -300 mV and NOx concentration was increased from 0 to 1000 μL/L , the best linearity and sensitivity of NOx sensor were 96.6% and 97.1% respectively, and its high temperature level was 1200 ℃. When NOx concentration was changed from 200 μL/L to 500 μL/L, the dynamic response time and recover time of NOx sensor were 25 s and 15 s, respectively. This kind of sensor showed good anti-disturbance to these gases, such as CO, SO2, formaldehyde, acetaldehyde, phenanthrene, acetone, and acrolein. The response current signal of NOx sensor was attenuated about 8.6%, when NOx sensor was applied continually on the automobile about 12 months, and its normal time was 5 months.

关 键 词：钙钛矿 电流型NOx传感器 喷雾热分解 敏感材料 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]