Jafari Nasim, Zeinali Sedigheh
Department of Nanochemical Engineering, School of Advanced Technologies, Shiraz University, Shiraz 7193615511, Iran.
ACS Omega. 2020 Feb 28;5(9):4395-4402. doi: 10.1021/acsomega.9b03124. eCollection 2020 Mar 10.
Formaldehyde is a volatile organic compound (VOC) with extensive applications, volatility, and toxicity, which have made it an important risk to human health even at low concentrations. Therefore, rapid detection of formaldehyde vapors in the environment is a necessity. Herein, we introduce a resistive gas sensor based on zeolitic imidazolate framework-8/multiwalled carbon nanotube (ZIF-8/MWCNT) for detection of formaldehyde vapors at room temperature. In this sensor, a low amount of MWCNTs was used in order to improve the electrical conductivity of the porous nanoparticles of ZIF-8. The sensor was fabricated by deposition of a thin layer of the nanocomposite onto interdigitated electrodes, and its sensing ability was investigated on exposure to formaldehyde vapors. The obtained sensor showed sensitive and fast responses to different concentrations of formaldehyde, and the sensor response to formaldehyde was higher than toward some other VOCs, including methanol, ethanol, acetone, and acetonitrile. Furthermore, because of the hydrophobic nature of ZIF-8, the effect of relative humidity on the gas-sensing performance was insignificant, which proves that this sensor is suitable for use under humid conditions.
甲醛是一种挥发性有机化合物（VOC），具有广泛的应用、挥发性和毒性，即使在低浓度下也对人类健康构成重大风险。因此，快速检测环境中的甲醛蒸气是必要的。在此，我们介绍一种基于沸石咪唑酯骨架-8/多壁碳纳米管（ZIF-8/MWCNT）的电阻式气体传感器，用于在室温下检测甲醛蒸气。在该传感器中，使用少量的多壁碳纳米管以提高ZIF-8多孔纳米颗粒的电导率。通过将纳米复合材料的薄层沉积到叉指电极上制备传感器，并研究其在暴露于甲醛蒸气时的传感能力。所获得的传感器对不同浓度的甲醛表现出灵敏且快速的响应，并且该传感器对甲醛的响应高于对其他一些挥发性有机化合物，包括甲醇、乙醇、丙酮和乙腈。此外，由于ZIF-8的疏水性，相对湿度对气敏性能的影响不显著，这证明该传感器适用于潮湿条件下使用。
