Rh-catalyzed WO3 with anomalous humidity dependence of gas sensing characteristics
Rh-catalyzed WO3 with anomalous humidity dependence of gas sensing characteristics
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DOI：
10.1039/c4ra06654e
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发表时间：
2014-01-01
期刊：
影响因子：
3.9
通讯作者：
Lee, Jong-Heun
中科院分区：
文献类型：
--
作者：
Choi, Kwon-Il;Hwang, Su-Jin;Lee, Jong-Heun
挥发性有机化合物的传感在包括疾病诊断、食品和国土安全在内的许多领域都至关重要。然而，在高度潮湿的大气中，水蒸气对气体响应的显著恶化往往阻碍了敏感和可靠的气体检测。在此，我们报告了一种负载铑的WO3空心球化学电阻传感器，可以潜在地用于在高度潮湿的大气中分析丙酮气体。采用喷雾热解法制备了纯WO3和负载铑的WO3空心球。与未加载的WO3传感器相比，负载铑的WO3传感器在高湿度（80% RH）的气氛下也具有快速的丙酮响应（2s）、高灵敏度、良好的线性度、高稳定性、低检出限（40 ppb）和对丙酮的强选择性。有趣的是，只有n型负载铑的WO3传感器才会出现异常现象，在潮湿的大气中，电阻和气体响应增加。本文还讨论了Rh负载的传感机理。Rh负载对气体响应、选择性和响应动力学的显著改善为丙酮气体的检测提供了良好的应用前景。
The sensing of volatile organic compounds is crucial in a variety of fields including disease diagnosis, food, and homeland security. However, the significant deterioration of gas response by water vapors often hinders the sensitive and reliable gas detection in a highly humid atmosphere. Herein, we report an Rh-loaded WO3 hollow sphere chemiresistive sensor that can be potentially used for acetone gas analysis in a highly humid atmosphere. Pure WO3 and Rh-loaded WO3 hollow spheres are synthesized via a spray pyrolysis method. The Rh-loaded WO3 sensor achieved a fast acetone response (2 s), high sensitivity, good linearity, high stability, low detection limit (40 ppb) and strong selectivity to acetone even under a highly humid (80% RH) atmosphere, compared with the unloaded WO3 sensor. Interestingly, an abnormal phenomenon occurs only with the n-type Rh-loaded WO3 sensor, where the resistance and gas response increases in humid atmospheres. The sensing mechanism by Rh loading is also addressed. The unusual improvement of gas response, selectivity, responding kinetics by Rh loading shows a good potential for the detection of acetone gas.