Colorimetry-based system for gaseous carbon dioxide detection: Membrane optimization

• Type: Article in International Scientific Journal
• Date: 2020

Authors

Mendes, JP (Author) Other; Coelho, L (Author) FCUP; Carlos M Pereira (Author) FCUP; Jorge, PAS (Author) FCUP

Journal

Title: U.Porto Journal of Engineering

Vol. 6

Pages: 59-69

Publisher: Universidade do Porto. Faculdade de Engenharia

Indexing

Scopus - 1 Citation

Other information

Authenticus ID: P-00T-33C

DOI: 10.24840/2183-6493_006.002_0006

Abstract (EN): The study of sensing materials to the detection of carbon dioxide (CO2) was achieved using p-nitrophenol (pNPh) as a colorimetric indicator. The sensing material was polymerized (NPLn), functionalized with 3-triethoxysilyl propyl isocyanate (IPTES) which sensitivity was tested in the form of a membrane as is and encapsulated in hollow silica nanoparticles. The sensing membranes were tested in a closed gas system comprising very precise flow controllers to deliver different concentrations of CO2 (vs. N2). The combination of the sensing membranes with multimode optical fibers and a dual-wavelength diode (LED) allows the measurement of the CO2 through the analysis of the induced absorbance changes with a self-referenced ratiometric scheme. The analysis of the sensing materials have shown significant changes in their chemical and physical properties and the results attest these materials with a strong potential for assessing CO2 dynamics in environmental, medical, and industrial applications.

Language: English

Type (Professor's evaluation): Scientific