Fabrication and carbon monoxide sensing characteristics of mesostructured carbon gas sensors

Abstract

We demonstrated a micro-chemoresistive gas sensing device using mesoporous carbon as the sensitive film and immobilized by dielectrophoresis (DEP) process. The mesoporous materials were characterized by X-ray diffraction (XRD) patterns, N(2) adsorption-desorption isotherms, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). N(2) adsorption-desorption isotherms shows the specific surface area of 1200 m(2)/g, total pore volume is 1.2 cm(3)/g of the mesoporous carbon, and the pore size distribution of mesoporous carbon yields an average pore size of 3 nm. SEM images show a rod-like morphology and TEM images show a highly ordered pore channel with linear arrays. CO gas sensor properties were measured and the resulting sensitivities were 5.7, 6.8, 8.8, 11.6, and 37.6% for concentrations of 30, 45, 60, 75, and 90 ppm. respectively. Additionally, this sensor also exhibited high sensitivity and fast response times for CO gas. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.