Turkish Journal of Chemistry
Abstract
This paper reports absorption-based CO_2 sensing of the pH-active Schiff base 2-[(2-hydroxymethylphenylimino) methyl]-5-bromo-phenol (SB) in an ethyl cellulose (EC) matrix with and without Teflon coating. The CO_2 sensitivity of the SB dye in the EC matrix was evaluated in the presence of nonadecafluorodecanoic acid and tetrabutyl ammonium hydroxide. When exposed to CO_2, the sensing films exhibited 76% of overall relative signal change and responded to CO_2 over a wide range: 1%-100 % (v/v). However, the slope of the spectral response between 1% and 5% (v/v) is more significant. The response time (\tau_{90}) was 15 s, and limit of detection (LOD) was 0.3% (v/v) CO_2. The stability of SB in the EC matrix was excellent, and when stored in the ambient air of the laboratory there was no significant drift in signal intensity after 6 months. Our stability tests are still in progress.
DOI
10.3906/kim-1006-675
Keywords
Absorbance, carbon dioxide, CO_2, gas sensor, Schiff base
First Page
503
Last Page
514
Recommended Citation
TOPAL, S. Z, ERTEKİN, K, YENİGÜL, B, & ERÇAĞ, A (2012). A new absorption based CO_2 sensor based on Schiff base doped ethyl cellulose. Turkish Journal of Chemistry 36 (4): 503-514. https://doi.org/10.3906/kim-1006-675