Zhou Tingting, Dong Wenbo, Qiu Yue, Chen Shiyu, Wang Xiaoxia, Xie Changsheng, Zeng Dawen
State Key Laboratory of Material Processing and Die & Mould Technology, Department of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China.
ACS Appl Mater Interfaces. 2021 Nov 17;13(45):54589-54596. doi: 10.1021/acsami.1c16637. Epub 2021 Nov 8.
It is important for noninvasive diagnosis of diabetes to develop acetone gas sensors with high selectivity. ZnO@ZIF-71 has been reported as a highly sensitive and selective gas sensor on acetone detection. However, it is difficult to exclude the interference with similar molecular sizes gas in the gas-sensing process, like ethanol. To solve this problem, polydimethylsiloxane (PDMS) was synthesized on the surface of ZnO@ZIF-71 to form a ZnO@ZIF-71@PDMS sensor by vapor deposition. The new sensor shows inert response to ethanol and effective response to acetone simultaneously. The PDMS membrane acts as a molecular sieve, which shows the acetone selectivity performance and can totally eliminate the response to low concentration ethanol at low temperature. Theory calculations and solubility test are also employed to prove the role PDMS plays in this process. It demonstrated that the acetone selectivity performance comes from the hydrogen bond interaction between the ethanol gas molecules and PDMS, which increases difficulty for ethanol gas molecules to penetrate the PDMS membrane. Further, this work provides a new method for enhancing gas-sensing selectivity and promoting for miniaturization of gas sensors.
开发具有高选择性的丙酮气体传感器对于糖尿病的无创诊断至关重要。据报道，ZnO@ZIF-71是一种对丙酮检测具有高灵敏度和选择性的气体传感器。然而，在气敏过程中难以排除与分子尺寸相似的气体（如乙醇）的干扰。为了解决这个问题，通过气相沉积在ZnO@ZIF-71表面合成聚二甲基硅氧烷（PDMS），形成ZnO@ZIF-71@PDMS传感器。新传感器对乙醇呈现惰性响应，同时对丙酮具有有效响应。PDMS膜起到分子筛的作用，表现出丙酮选择性性能，并且能够在低温下完全消除对低浓度乙醇的响应。理论计算和溶解度测试也被用于证明PDMS在此过程中所起的作用。结果表明，丙酮选择性性能源于乙醇气体分子与PDMS之间的氢键相互作用，这增加了乙醇气体分子穿透PDMS膜的难度。此外，这项工作为提高气敏选择性和推动气体传感器小型化提供了一种新方法。
