Room temperature trimethylamine gas sensor based on aqueous dispersed graphene
Authors: Raola RAG., Concina I., Sevilla FB., Ferroni M., Sangaletti L., Sberveglieri G., Comini E.
Autors Affiliation: Univ Santo Tomas, Grad Sch, Manila, Philippines; Univ Brescia, Dept Informat Engn, CNR, INO SENSOR, I-25133 Brescia, Italy; Univ Santo Tomas, Res Ctr Nat & Appl Sci, Manila, Philippines; Univ Cattolica Sacro Cuore, Dept Math & Phys, Brescia, Italy
Abstract: A water dispersible graphene polymer nanocomposite was synthesized by solution blending method and deposited on a nylon-6 membrane via vacuum assisted self-assembly (VASA) method to fabricate a flexible material applied as a chemoresistive gas sensor for trimethylamine (TMA). The morphological and structural characterization of graphene/polystyrene-sulfonate nanocomposite were carried out by using Fourier-Transform infrared (FT-IR) spectroscopy, Raman spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy and field-effect scanning electron (FE-SEM) microscope. While, electrical conductivity was measured using a four-point probe measurement. The prepared polymer nanocomposite has a percolation threshold around 0.30% vol. fraction, with a conductivity of 2.45 S/m (rsd = 3.0%, n=3). The response of the composite sensor exhibited linear range from 23 to 183 mg/L (r(2)=0.95713) and the sensitivity was at 1.72 x 10(-3) Delta R/R mg L-1. The gas sensor exhibited repeatable response to TMA gas and the calculated limit of detection was at 22.67 mg/L.
KeyWords: graphene; polymer nanocomposites; trimethylamine & chemiresistor