Comparison of Electrical and Sensing Properties of Pure, Sn- and Zn-Doped CuO Gas Sensors

In this paper, the evaluation of the gas sensing performance of chemoresistive sensor devices based on M-doped CuO (M = Sn, Zn) nanoparticles prepared by a simple wet chemical method is reported. The morphology of samples has been assessed by scanning electron microscope and transmission electron microscope. The sensors were fabricated, depositing by drop coating the nanoparticles on the sensor substrate platform, and the electrical performance upon exposure to different gases in the air was recorded. The CuO-based gas sensors present a p-type semiconductor behavior. The results of electrical tests have shown that Sn and Zn effectively act as promoters improving the gas sensing properties of CuO toward some volatile organic compounds such as acetone and ethanol. Zn-CuO sensor resulted the most sensitive and selective to acetone, revealing that the appropriate choice of dopant plays a key role in the design of CuO-based sensors.