title: The template-free synthesis of square-shaped SnO(2) nanowires: the temperature effect and acetone gas sensors.
abstract: Square-shaped single-crystalline SnO(2) nanowires and their sphere-like hierarchical structures were synthesized successfully with a template-free hydrothermal approach. It was found that an intermediate phase-Na(2)Sn(OH)(6)-is first produced because it is slow to dissolve in ethanol/water media. The intermediate phase gradually decomposes and converts into SnO(2) at temperatures higher than 200 °C. The reaction temperature also affects the microstructure of SnO(2) nanomaterials. Uniform square-shaped SnO(2) nanowires, which form sphere-like hierarchical structures in 100% structure yield, can be produced at 285 °C on a large scale. The diameter of the nanowires shows a decrease accompanying the increase of the reaction temperature. The temperature effect could be a result of the faster and oriented growth of SnO(2) nanowires along their [Formula: see text] direction at higher temperature. Chemical sensors constructed with square-shaped SnO(2) nanowires exhibit excellent stability, good sensitivity and selectivity, as well as a quick response and short recovery times under exposure to acetone gas in practical applications.
authors.affiliation: Department of Chemistry, College of Science, Shanghai University, Shanghai 200444, People's Republic of China.
authors.forename: Lipeng
authors.initials: L
authors.lastname: Qin
authors.forename: Jiaqiang
authors.initials: J
authors.lastname: Xu
authors.forename: Xiaowen
authors.initials: X
authors.lastname: Dong
authors.forename: Qingyi
authors.initials: Q
authors.lastname: Pan
authors.forename: Zhixuan
authors.initials: Z
authors.lastname: Cheng
authors.forename: Qun
authors.initials: Q
authors.lastname: Xiang
authors.forename: Feng
authors.initials: F
authors.lastname: Li