A miniature chemiresistor sensor for carbon dioxide

Sira Srinives; Tapan Sarkar; Raul Hernandez; Ashok Mulchandani

doi:10.1016/j.aca.2015.03.020

A miniature chemiresistor sensor for carbon dioxide

Anal Chim Acta. 2015 May 18:874:54-8. doi: 10.1016/j.aca.2015.03.020. Epub 2015 Mar 18.

Authors

Sira Srinives¹, Tapan Sarkar¹, Raul Hernandez¹, Ashok Mulchandani²

Affiliations

¹ Department of Chemical and Environmental Engineering, University of California-Riverside, Riverside, CA 92521, USA.
² Department of Chemical and Environmental Engineering, University of California-Riverside, Riverside, CA 92521, USA. Electronic address: adani@engr.ucr.edu.

PMID: 25910446
DOI: 10.1016/j.aca.2015.03.020

Abstract

A carpet-like nanostructure of polyaniline (PANI) nanothin film functionalized with poly(ethyleneimine), PEI, was used as a miniature chemiresistor sensor for detection of CO2 at room temperature. Good sensing performance was observed upon exposing the PEI-PANI device to 50-5000 ppm CO2 in presence of humidity with negligible interference from ammonia, carbon monoxide, methane and nitrogen dioxide. The sensing mechanism relied on acid-base reaction, CO2 dissolution and amine-catalyzed hydration that yielded carbamates and carbonic acid for a subsequent pH detection. The sensing device showed reliable results in detecting an unknown concentration of CO2 in air.

Keywords: Carbon dioxide; Conducting polymer; Gas sensor; Poly(ethyleneimine); Polyaniline.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aniline Compounds / chemistry*
Carbon Dioxide / analysis*
Equipment Design
Humidity
Hydrogen-Ion Concentration
Nanostructures / chemistry*
Nanostructures / ultrastructure
Polyethyleneimine / chemistry*
Temperature

Substances

Aniline Compounds
polyaniline
Carbon Dioxide
Polyethyleneimine