Development of Cost-Effective, Selective and Stable Room Temperature Methanol Sensor

Abstract

In the present work, the structural and morphological of 5, 10, 15, 20 tetratoloylphenylporphyrinato Zinc (II) (ZnTTP) thin films prepared by spin coating on low cost glass substrate have been investigated using X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). At room temperature, the electrical responses of ZnTTP thin films were measured under five reducing volatile organic compounds, including toluene, acetone, methanol, ethanol, and isopropanol. The obtained results indicate that the ZnTTP behaves as a p-type semiconductor. The developed sensor exhibits the highest linear response with methanol vapor. The selective methanol sensor based on ZnTTP thin film reveals a good reproducibility, great stability for more than 28 days, and a limit of detection as low as 2 ppm. At 260 ppm, it has fast response and recovery times of 51 s and 92 s, respectively. The principal component analysis (PCA) treatment was successfully used to discriminate methanol vapor.