Experimental and theoretical studies of Zn-doped MoO3 hierarchical microflower with excellent sensing performances to carbon monoxide.

Four MoO 3 samples with the Zn element doped mole ratio of 0%, 3%, 6% and 9% were prepared by applying a convenient one-step hydrothermal synthesis method, and the samples presented three-dimensional microflower-like structures assembled by nanosheets. The systematic analysis results indicate that the 6 mol% Zn-doped sample had the most amazing detection characteristics for 50 ppm CO, with a response of 31.23 (4 times of the pure MoO 3) at a lower temperature (240 °C). The large specific surface area, big pore size and tiny particle size were proved to be beneficial to the gas sensitivity, which promotes gases transfer and provides more gases landing points during the gas-sensitive reaction. Besides, based on the density functional theory (DFT), the facilitation effect of doped Zn on the adsorption ability of MoO 3 to CO molecule was verified from the perspective of electronic properties. The excellent gas-sensing performances indicate that the 6 mol% Zn-doped MoO 3 has potential to be applied as a reliable CO sensor. [ABSTRACT FROM AUTHOR]