Preparation and gas sensing properties of hexagonal zinc oxide regulated by surface modification

Hexagonal ZnO nanocones were successfully synthesized by hydrothermal method, combined with active agents and other means of control, and calcined at 350 °C. Detailed testing and research were conducted on the crystal structure, micro morphology, optical properties, and growth mechanism of the samples using testing methods such as XRD, XPS, SEM, BET, UV and PL. The gas sensor based on hexagonal ZnO exhibits good gas sensitivity to ethylene glycol at the optimal operating temperature of 200 °C. The response value to 25 ppm ethylene glycol is as high as 350.3, and the response recovery time is about 48 s/104 s. Even the response to 5 ppm ethylene glycol reaches 55, and it exhibits excellent cyclic repeatability and selectivity. Finally, the gas sensing mechanism is analyzed in detail.