A new absorption based CO2 sensor based on Schiff base doped ethyl cellulose

Authors : Sevinç Zehra TOPAL, Kadriye ERTEKİIN, Berrin YENİIGÜL, Ayşe ERÇAĞ

Pages : 503-514

Doi:10.3906/sag-1210-97

View : 22 | Download : 8

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :This paper reports absorption-based CO2 sensing of the pH-active Schiff base 2-[insert ignore into journalissuearticles values(2-hydroxymethylphenylimino); methyl]-5-bromo-phenol insert ignore into journalissuearticles values(SB); in an ethyl cellulose insert ignore into journalissuearticles values(EC); matrix with and without Teflon coating. The CO2 sensitivity of the SB dye in the EC matrix was evaluated in the presence of nonadecafluorodecanoic acid and tetrabutyl ammonium hydroxide. When exposed to CO2, the sensing films exhibited 76% of overall relative signal change and responded to CO2 over a wide range: 1%-100 % insert ignore into journalissuearticles values(v/v);. However, the slope of the spectral response between 1% and 5% insert ignore into journalissuearticles values(v/v); is more significant. The response time insert ignore into journalissuearticles values(t90); was 15 s, and limit of detection insert ignore into journalissuearticles values(LOD); was 0.3% insert ignore into journalissuearticles values(v/v); CO2. 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.
Keywords : Absorbance, carbon dioxide, CO2, gas sensor, Schiff base