Large-scale synthesis and quantitative characterization of size-controllable potassium tungsten bronze nanowires

作者:Liu, Chang; Peng, Yuehua; Zhou, Fang; Yin, Yanling; Huang, Xingqing; Wang, Lizhou; Wang, Weike; Zhou, Weichang; Tang, Dongsheng*
来源:Journal of Physics D: Applied Physics , 2018, 51(9): 095305.
DOI:10.1088/1361-6463/aaa9dd

摘要

Single-crystalline hexagonal potassium tungsten bronze K0.26WO3 nanowires with diameters of 10-30 nm and lengths to several micrometers have been successfully synthesized via a hydrothermal method. The diameters of K0.26WO3 nanowires can be well modulated by reducing potassium tungsten oxide K2OW7O21 nanowires in hydrogen atmosphere at different temperatures. X-ray quantitative characterization indicates that the lattice constants and crystal lattice microstrains of these K0.26WO3 nanowires exhibit anisotropic behaviors along the radial and axis directions, which can be well explained by the surface effect and K+ ion aggregating or ordering. It also indicates that oxygen vacancies will occur in the WO3 lattice when the reduction temperature is around 650 degrees C, and the oxygen vacancies will prevent K+ ions from aggregating or ordering. Controllable synthesis and quantitative analysis of size-controllable KxWO3 nanowires will contribute to deepen our understanding on their structures and properties, and explore their potential applications in nanoscale resistive switching devices based on the distribution of K+ ions.