Chitin‐Based Functional Films for the Colorimetric Detection of Ethylene Glycol

Abstract

We developed a new method for producing large‐area color thin films for the colorimetric detection of ethylene glycol. This method is based thermal evaporation of chitin. This process enables easy manipulation of the thickness and color patterns of the film by using shadow masks and repeated evaporation. We used this film to demonstrate a colorimetric sensor for the detection of ethylene glycol gas. The use of chitin allows the manufacture of inexpensive and environment‐friendly gas detectors. When the film was exposed to target gas, the film reacted with ethylene glycol and hydroxyl group on the chitin‐film by etherification. Then the films underwent both chemical and structural changes, resulting in color changes at low ppm concentrations. We were able to compare the sensor reaction to gases with and without the hydroxyl group. The selectivity of the sensor was confirmed by analyzing the gas containing the hydroxyl group through the linear discriminant analysis (LDA) method. We expect that our results will be utilized to provide low‐cost and low‐power systems for gas monitoring.This article is protected by copyright. All rights reserved.