The effect of NO2 doping on the gas sensing properties of copper phthalocyanine thin film devices

In this work we report the effect on the NO2 gas sensing properties of initially doping CuPc thin films with oxygen (in air) and NO2 for room temperature operation. The pre-treatment with NO2 is shown to improve the gas sensing properties by providing both an increase in the magnitude of the conductivity change for a given NO2 concentration and a significant improvement in the recovery time. Data presented suggest that a simple time derivative of the change in current may provide a measure of concentration for real time gas sensing applications