摘要
对中温固体氧离子导体———La0.9Sr0.1Ga0.8Mg0.2O2.85材料分别在1300,1350,1400和1450℃4个温度下烧结4 h,之后对其进行XRD,SEM和阻抗谱等测试。实验结果显示:当烧结温度为1400℃时,样品为单一的La0.9Sr0.1Ga0.8Mg0.2O2.85晶体相,晶粒排列较为紧密,致密度达到96.6%,且不同温度下的电导率均最高。然后,选取在该温度下烧结的大小不同的两片陶瓷片制作了一种新型结构的电流型氧传感器。改变测试环境中的氧浓度的大小,在600,650和700℃3个温度下对传感器的气敏特性进行了测试。从测试的结果中发现:传感器极限电流与氧浓度并不呈现传统的线性关系。根据Fick第一定律、法拉第定律和Langmuir吸附方程对这种氧传感器的极限电流与氧浓度的关系进行了理论推导,得到了新的关系表达式,实验结果也验证了理论推导出的结果的合理性。此外,在温度为600℃时,对该传感器的响应时间进行了测试,上升和下降响应时间均为10～15 s。
The intermediate-temperature solid oxygen conductor-La0.9Sr0.1Ga0.8Mg0.2O2.85 was sintered at 1300,1350,1400 and 1450 ℃ for 4 h,respectively.The tests of the sintered ceramics,such as XRD,SEM,impedance spectroscopy and so on were performed.From the tested data,it could be found that the ceramics only contained the La0.9Sr0.1Ga0.8Mg0.2O2.85 crystal phase when the sintered temperature was 1400 ℃,whose grains arranged closely and the relative density reached 96.6%.Furthermore,it′s conductivity at different temperature were all the highest.The ceramics with two different sizes were selected to make the oxygen sensor.And the sensor was tested in the different oxygen concentration environment when tested temperatures were 600,650 and 700 ℃,respectively.It could be find that the limiting currents did not present the traditional linear relationship depended on the oxygen concentration.According to Fick′s first law,Faraday′s law and Langmuir adsorption equation,the new relationship between them was worked out.And the experiment data also verified the new theoretical derivation relationship.In addition,the response time of the sensor was tested at 600 ℃.The rise and fall response times were all 10 to 15 s.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2013年第1期90-95,共6页
Journal of the Chinese Society of Rare Earths
基金
博士后科学基金会项目(20100470735)
