title: Orientated Langmuir-Blodgett assembly of VO(2) nanowires.
abstract: We report Langmuir-Blodgett (LB) based assembly of vanadium dioxide (VO(2)) nanowires. VO(2) nanowires were functionalized with stearic acid (SA) and cetyltrimethylammonium bromide (CTAB) and then spread on the surface in an aqueous phase in a LB trough. Surface pressure-area (pi-A) isotherms were recorded on the LB trough and show hysteretic behavior. Scanning electron microscopy investigations of morphology and alignment of the VO(2) nanowire films transferred at different points on the pi-A curve demonstrate that with increasing surface pressure there is a transition from well-separated domains of nanowires to compact and locally ordered nanowire monolayers, while aggregates of raftlike nanowire structures remain after expansion. Interestingly, X-ray diffraction studies show that VO(2) nanowire LB films exhibit (00l) crystal plane orientation, which is attributed to preferential coordination of SA and CTAB-SA complex to (001) surface of VO(2) nanowires thereby driving this orientation.
authors.affiliation: School of Materials Science and Engineering, Wuhan University of Technology, Wuhan, 430070, China. mlq@cmliris.harvard.edu
authors.forename: Liqiang
authors.initials: L
authors.lastname: Mai
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Gu
authors.forename: Chunhua
authors.initials: C
authors.lastname: Han
authors.forename: Bin
authors.initials: B
authors.lastname: Hu
authors.forename: Wen
authors.initials: W
authors.lastname: Chen
authors.forename: Pengchao
authors.initials: P
authors.lastname: Zhang
authors.forename: Lin
authors.initials: L
authors.lastname: Xu
authors.forename: Wanli
authors.initials: W
authors.lastname: Guo
authors.forename: Ying
authors.initials: Y
authors.lastname: Dai
mesh_terms: D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure; D010100:Oxygen / Q000737:chemistry*; D017968:Vanadium Compounds / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D017968:Vanadium Compounds; D010100:Oxygen