CO gas sensor based on a conducting dendrimer

This paper presents the results of the gas-sensing performance of a siloxane-based dendrimer gas sensor. We have synthesized a suitable dendrimer for sensing CO gas, and fabricated a device by spin-coating the dendrimer. For the source and drain contact, we deposited Au by thermal evaporation. The sensor linearly responded to the various concentrations of CO gas. The higher CO gas concentration became, the higher the current was produced. The current was proportional to the CO concentrations, although it tends to gradually saturate above 40% of concentration. For the transient characteristics, it took about 250 s to reach 90% of the steady-state value when CO gas turns on. The recovery time to the baseline was about 420 s after the gas turns off. The current conduction mechanism of the dendrimer-based sensor was found to be determined by interference of CO gas between the surface functional groups of dendrimer.