Investigation of sensitivity and selectivity of ZnO thin film to volatile organic compounds

Abstract

This research addresses a detailed study on the sensitivity and selectivity of ZnO thin film to volatile organic compound (VOC) vapors that can be used for the development of VOC sensors. The ZnO thin film of 100 nm thickness was prepared by post-annealing of e-beam evaporated Zn thin film. The sample was structurally, morphologically, and chemically characterized by X-ray diffraction and field emission scanning electron microscopy analyses. The sensitivity, selectivity, and detection limit of the sample were tested with respect to a wide range of common VOC vapors, including acetone, formaldehyde, acetic acid, formic acid, acetylene, toluene, benzene, ethanol, methanol, and isopropanol in the temperature range of 200-400°C. The results show that the best sensitivity and detection limit of the sample are related to acetone vapor in the studied temperature range. The ZnO thin film-based acetone sensor also shows a good reproducibility and stability at the operating temperature of 280°C.

Semiconductor Metal Oxides as Chemoresistive Sensors for Detecting Volatile Organic Compounds

“…The increased emissions of VOCs have an adverse influence on the ambient air [4,5,6,7,8]. Moreover, certain volatile organic compounds are identified as hazardous gases and can cause severe diseases such as allergy, colon cancer, rectal cancer, and lung cancer [9]. Therefore, environmental monitoring is essential for evaluating the air quality [10,11,12,13,14].…”

Thin Films of an Ultrastable Metal–Organic Framework for Formic Acid Sensing with High Selectivity and Excellent Reproducibility

“…Furthermore, the sensor possesses a good repeatability response to 3.2 × 10 –4 mol/L formic acid vapor, confirmed by the high similar response-recovery curves of each test cycle (Figure d) as well as the negligible degradations in response value and response time during the successive tests (see Figure , as well as Figure S4 in the Supporting Information). In particular, the MOF-802 thin-film sensor achieved the effective detection of formic acid vapor at room temperature, which is superior to the previously well-studied sensors based on metal-oxide semiconductors with much higher operation temperatures. ,, The MOF thin-film sensor we developed has great potential for formic acid vapor detection applications in civil and industrial fields.…”

“…In particular, the MOF-802 thin-film sensor achieved the effective detection of formic acid vapor at room temperature, which is superior to the previously well-studied sensors based on metal-oxide semiconductors with much higher operation temperatures. 9,22,23 The MOF thin-film…”