Laser patterned platform with PEDOT-graphene composite film for NO2 sensing

This work presents a simple and fully electrochemical route used for fabricating of a NO2 gas sensor made of reduced-graphene-oxide-poly(3,4-ethylenedioxythiophene) composite film. The sensing platform was fabricated from alumina substrate and equipped with gold interdigitated electrodes and built-in heater. The temperature distribution on the surface of interdigitated electrodes was investigated by a thermal imaging camera and compared with numerical simulations. The sensing film was prepared on sensing platform by electropolymerization of EDOT monomer and graphene oxide solution and reduction in 0.1 M KCl. A scanning electron microscopy and Raman spectroscopy of the sensing film were performed. Gas sensing measurements were carried out at elevated temperatures. The effects of the operating and annealing temperature of the gas sensing film to NO2 on the sensing performance were investigated. The response characteristics in NO2 at elevated temperatures in a tube furnace and using a built-in heater were compared. The effect of the flow rate and relative humidity was also investigated.