Effect of doping on the morphology and dimethylamine gas sensing properties of hexagonal pine needle-like WO3 structures with highly exposed (100) facet.

Schematic illustration of the synthesis process of hexagonal pine needle-like Sn-WO 3 structures. [Display omitted] • Hexagonal pine needle-like Sn-WO 3 structures were prepared via a hydrothermal method. • The Sn/W ratios play an important role in the morphology and phase of hexagonal pine needle-like Sn-WO 3 structures. • The gas sensor based on hexagonal pine needle-like Sn-WO 3 structures exhibits excellent sensing properties to dimethylamine. Novel hexagonal pine needle-like Sn-WO 3 structures were synthesized using the hydrothermal method. The present study aimed to evaluate the impact of Sn/W ratios and the introduction of several metal elements (Fe, Zn, Cu, and In) on both the morphology and gas-sensing properties of WO 3. The hexagonal pine needle-like 1 % Sn-WO 3 sensor had a significantly elevated response of 89 and a faster response/recovery time of 11/15 s when exposed to 10 ppm dimethylamine (DMA) at the optimal operating temperature of 180 °C. This sensor displayed notable characteristics such as excellent selectivity, repeatability, long-term stability, and a detection limit of 25 ppb. The excellent sensing performances of this sensor can be attributed to their highly (1 0 0) facet, Sn doping and distinctive hexagonal pine needle-like morphology. [ABSTRACT FROM AUTHOR]