Porous α-Fe2O3 gas sensor with instantaneous attenuated response toward triethylamine and its reaction kinetics
Porous α-Fe2O3 gas sensor with instantaneous attenuated response toward triethylamine and its reaction kinetics
复制标题
对三乙胺瞬时衰减响应的多孔α-Fe2O3气体传感器及其反应动力学
DOI：
10.1016/j.cej.2021.131631
复制
发表时间：
2021-08-18
影响因子：
15.1
通讯作者：
Duan, Guotao
中科院分区：
文献类型：
--
作者：
Wang, Hong;Luo, Yuanyuan;Duan, Guotao
在相对较低的温度下实现三乙胺（TEA）的高选择性和快速检测仍然具有挑战性。在这项工作中，我们报告了一个超灵敏的TEA气体传感器与特定的响应的基础上的多孔α-Fe 2 O3空心球阵列，其中外壳是由纺锤形颗粒。在较低的工作温度（160 ℃）下，该传感器对10 ppm TEA显示出高响应（75.8），响应时间短（2 s），并且可以检测低至50 ppb的TEA。更重要的是，在TEA检测期间观察到明显的衰减特性。当操作温度超过阈值（>120摄氏度）时，这种对TEA气体的独特响应是可重复的。此外，瞬时衰减的响应被发现是独立的气体浓度和湿度，但与特定的气体，证明其潜力被用作特征信号，以实现高度选择性检测的TEA分子。此外，基于密度泛函理论（DFT）计算，衰减的响应可以归因于一个特殊的表面动力学反应过程，涉及TEA分子的热分解和氮氧化物的形成，这是由准原位X射线光电子能谱分析验证。这一工作为研制高选择性、高灵敏度的传感器提供了新的思路。
To achieve highly selective and rapid detection of triethylamine (TEA) at a relatively low temperature remains challenging. In this work, we report an ultrasensitive TEA gas sensor with a specific response based on the porous alpha-Fe2O3 hollow sphere array, which shell is composed of fusiform particles. At a low operating temperature (160 degrees C), the sensor shows high response (75.8) toward 10 ppm TEA with a short response time (2 s) and can detect TEA as low as 50 ppb. More importantly, an obvious attenuation characteristic is observed during TEA detection. This distinctive response toward TEA gas is repeatable when the operating temperature is over a threshold (>120 degrees C). Moreover, the instantaneous attenuated response is found to be independent of the gas concentration and humidity but much related to specific gases, demonstrating its potential to be used as a characteristic signal to achieve highly selective detection of TEA molecules. Furthermore, based on density functional theory (DFT) calculations, the attenuated response can be ascribed to a special surface dynamic reaction process involving the thermal decomposition of TEA molecules and the formation of nitrogen oxides, which is verified by the quasi in-situ X-ray photoelectron spectroscopy analysis. This work will provide a new idea for developing highly selective and sensitive sensors.