Degradation mechanism of TiO2 based lambda oxygen sensor poisoned by phosphorus
Degradation mechanism of TiO2 based lambda oxygen sensor poisoned by phosphorus
复制标题
磷中毒TiO2基氧传感器的降解机理
DOI：
10.1016/j.snb.2018.04.095
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Li Zhimin
中科院分区：
文献类型：
--
作者：
Zhang Maolin;Ning Tao;Sun Peng;Zhang Dongyan;Yan Yangxi;Li Zhimin
TiO2 因其优异的气体传感特性而成为汽车空燃比 (A/F) 氧传感器最常用的材料之一。众所周知，汽油的成分非常复杂，多种汽油中都含有微量的含磷添加剂。许多研究表明，失效的氧传感器表面负载有大量含磷颗粒。然而，很少有研究关注磷对TiO2传感膜的影响。本工作制备了纯TiO2和P2O5污染的TiO2氧传感器，探讨了磷对TiO2传感膜的影响。结果表明，当TiO2被P2O5中毒时，传感器的瞬态响应受到显着影响。利用 XRD、SEM、EDS 和 XPS 分析了 P2O5 中毒后 TiO2 传感膜的相结构、形貌和表面化学状态。研究发现TiO2表面被磷酸根包覆，在颗粒表面形成阻挡层，阻止电子向O2分子的转移。
TiO2is one of the most popular materials used as air/fuel ratio (A/F) oxygen lambda sensor for automobiles, because of its excellent gas sensing properties. As is well known, the composition of gasoline is very complex and trace amounts of phosphorus-containing additives are present in many kinds of gasoline. Many studies have shown that a large amount of phosphorus containing particles is loaded on the surface of the failed oxygen sensor. However, few studies have focused on the effects of phosphorus on the TiO2sensing film. In this work, pure TiO2and P2O5contaminated TiO2oxygen lambda sensor were prepared to discuss the effects of phosphorus on TiO2sensing film. The results showed that the transient response of the sensor is significantly affected when TiO2is poisoned by P2O5. XRD, SEM, EDS and XPS were used to analyze the phase structure, morphology and surface chemistry state of TiO2sensing film poisoned by P2O5. It is found that the TiO2surface was coated by phosphate radical, resulting in a barrier layer on the grain surface which blocks the transfer of electrons to O2molecule.