Ammonia classified as one of the hazardous chemical to environment and human. Therefore, monitoring the ammonia in air is vital. Chitosan film was selected as a sensing material for ammonia detection in this study. Chitosan powder was dissolved in 2% of acetic acid to form chitosan solution gel. It was subsequently deposited on patterned electrode by using electrochemical deposition technique. The response of the chitosan sensor towards ammonia was tested via electrical testing by exposing different ammonia concentration ranging from 20 ppm, 100 ppm, 200 ppm, and 300 ppm using air exposure technique. The response of the chitosan sensor towards ammonia was recorded as output voltage. Sensor properties which include sensitivity, stability, recovery, and repeatability were studied. The electrical result showed that the response of chitosan sensor increases as the ammonia concentration increases. All the sensing properties were achieved. Finally, 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.

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.

In this study, the effect of spinach-ferredoxin addition in chitosan matrix towards optical band gap was investigated. 5 distinct solutions were prepared by blending chitosan and spinach-ferredoxin (Cs-Fdx) with the volume to volume ratios of 100:0, 95:5, 90:10, 85:15 and 80:20 respectively. The solutions were cast into film via spin coating technique. The optical properties in terms of absorbance for these films were investigated using UV-Vis Spectrometer. UV-Vis result showed that the absorbance increased as the spinach-ferredoxin content increases. Finally, the optical band gaps of the films were determined by extrapolating a straight line of (αhν)2vs. hν curves. Band gap value of 3.48 eV, 3.25 eV, 3.2 eV, 3.0 eV, and 2.8 eV were observed for (Cs-Fdx) films with 100:0, 95:5, 90:10, 85:15 and 80:20 respectively.