Fabrication and carbon monoxide sensing characteristics of mesostructured carbon gas sensors

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, N2 adsorption–desorption isotherms, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). N2 adsorption–desorption isotherms shows the specific surface area of 1200 m2/g, total pore volume is 1.2 cm3/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.