Ammonia Gas Sensor Based on Chitosan Biopolymer

Abstract

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.

Ultrasensitive Gold Nanostar–Polyaniline Composite for Ammonia Gas Sensing

“…36,52,53 Even a gold−bio composite used in ammonia sensing has been reported. 54 Here, the sensing action based on a change in the resistance of the nanocomposite film due to exposure to ammonia has been used, thus making it simpler to fabricate and use inexpensively. PANI was used because it is a low-cost, readily available, biocompatible, easy to process polymer.…”

“…Gold nanostars (average size ∼170 nm) were synthesized via a colloidal chemical method and consisted of polyaniline solution to make a thin film on a glass substrate by spin coating. Ammonia sensors employing nanoparticle–polymer composites have also been reported. ,, Even a gold–bio composite used in ammonia sensing has been reported . Here, the sensing action based on a change in the resistance of the nanocomposite film due to exposure to ammonia has been used, thus making it simpler to fabricate and use inexpensively.…”

Development of a Chitosan/Nickel Phthalocyanine Composite Based Conductometric Micro‐sensor for Methanol Detection

“…However, the main properties of phthalocyanines in detection abilities for environmentally relevant volatile organic compounds are particularly, their ionization potentials ability, which can as well be varied by metalion insertion and besides by the attachment of other atoms or groups that trigger or diminish the ionization potential in preference of their position in the electronegativity scale [25]. An important approach to get control of some of the physical limitations of most phthalocyanines, including the bad processability and higher crystallinity for chemosensing, comprises combining these materials with polymers [26], such as polyvinyl alcohol (PVA), polystyrene, (PS), polymethyl methacry-late (PMMA) [27], etc. Phthalocyanines are functionalized in the polymer through dissolution, in a common solvent and deposited by a common solution processing.…”

Electrospun PVC-nickel phthalocyanine composite nanofiber based conductometric methanol microsensor

“…Originally, non-invasive analytical pieces of equipment such as PTR-MS (Proton Transfer Reaction/Mass Spectrometry), GC-MS (Gas Chromatography/Mass Spectrometry), and chemiluminescence gas analyzers were known for methanol detection and measurements for early diagnostic techniques [3]. With these techniques, conventional VOC analysis becomes time-consuming, expensive, and unsuited for extensive screening [4].…”