In this study, zinc oxide (ZnO) nanorod arrays (NRAs) coated with carbon material were fabricated onto a silicon substrate through a hydrothermal method followed by chemical vapour deposition. A series of tests were carried out, including crystallinity analysis, microstructure observation and investigation of the luminescent and electrical properties. Further, a nanosensing device for UV light and carbon monoxide (CO) was constructed through fabrication of a Schottky contact. The sensing abilities of the zinc oxide NRA devices before and after carbon coating were compared. The sensing mechanism was also investigated. Results indicated that hte carbon coating was amorphous, with high mechanical strength, specific light transmittance and high resistance to chemical corrosion. After coating with carbon, the zinc oxide nanorods retained their original structure. In the UV light sensing test, the carbon layer retarded the electron transport, but the carbon-coated NRA device showed a higher average current in response to UV light compared to the bare NRA device. In the CO sensing experiment, the carbon coating provided functional groups for CO adsorption and improved the sensitivity.
