Chloroform Gas Sensor Based on Chitosan Biopolymer

Abstract

Chloroform classified as one of the hazardous chemical to human. Therefore, monitoring the chloroform concentration in air is vital. In this study, chitosan powder was dissolved in 2% of acetic acid to form chitosan solution gel. It was subsequently deposited on printed circuit board (PCB) by using electrochemical deposition technique. The response of the chitosan sensor towards chloroform was tested via electrical testing by exposing different chloroform concentration ranging from 10 ppm, 20 ppm, 30 ppm, 40 ppm, and 50 ppm using air exposure technique. The response of the chitosan sensor towards chloroform was recorded as output voltage. Sensing properties of the chitosan sensor which include sensitivity, stability, recovery, and repeatability were studied. The electrical result showed that output voltage increases as the concentration of chloroform increases. All the sensing properties were achieved. The structure characterization of the chitosan was studied using Fourier Transform Infrared Spectroscopy (FTIR). The appearance of N-H and O-H groups in FTIR spectrum of chitosan film provides evidence that the domain functional group exist in chitosan after it was processed into film.