Nanoporous In2O3-based cataluminescence sensor for acetic acid vapor

In the present paper, we reported a cataluminescence (CTL) sensor using nanoporous In₂O₃ as sensing material to determine trace acetic acid in air. The proposed sensor showed high sensitivity and selectivity to acetic acid at optimal temperature of 293degC. Quantitative analysis was performed at a wavelength of 440 nm. The linear range of CTL intensity versus concentration of acetic acid are 25 mL/m³ to 500 mL/m³ and 501 mL/m³ to 2500 mL/m³, with detection limit of 8 mL/m³. No or only very low levels of interference was observed while the coexistence of other gases passing through the sensor. Formic acid, ethanol, acetaldehyde, formaldehyde, benzene, toluene, and n-hexane caused interference at around 2.7%, 4.5%, 10.8%, 2.0%, 2.9%, 2.7% and 2.3%, respectively. Chloroform and ammonia vapors did not show any interference. The technique has been successfully applied to determine acetic acid in the artificial air samples.