CuO nanoparticles fabricated by direct thermo-oxidation of sputtered Cu film for VOCs detection

Abstract

The integrated CuO nanoparticles based sensor is fabricated by direct thermal oxidation of the magnetron sputtered Cu film on the commercial planar sensor substrate without the conventional coating procedure. In comparison, the CuO nanoparticles and CuO nanowires sensors prepared by facile solution method are also fabricated by manual coating of the as-prepared materials on the cylindrical substrate, respectively. The results of the sensing measurements show that the integrated sputtered CuO nanoparticles sensor exhibits the highest and fastest response toward 20–500ppm ethanol vapor at 200°C than that of the other two well-coated CuO nanostructured sensors, with response time of 4–10s and recovery time of 4–8s. The as-deposited CuO nanoparticles sensor also shows good selectivity, reproducibility and reversibility toward ethanol at 200°C. The sensing properties of the integrated CuO nanoparticles sensor toward a series of chlorinated volatile organic compounds (VOCs) are also investigated. The as-deposited CuO sensor exhibits anomalous resistance decrease upon exposure to 20–500ppm CCl4 vapor which is different with the resistance increase when exposed to any other examined reducing target. It is believed that the integrated CuO nanoparticles sensor may be a promising candidate for VOCs sensing applications.