title: Direct observation of melting behaviors at the nanoscale under electron beam and heat to form hollow nanostructures.
abstract: We report the melting behaviours of ZnO nanowire by heating ZnO-Al(2)O(3) core-shell heterostructures to form Al(2)O(3) nanotubes in an in situ ultrahigh vacuum transmission electron microscope (UHV-TEM). When the ZnO-Al(2)O(3) core-shell nanowire heterostructures were annealed at 600 °C under electron irradiation, the amorphous Al(2)O(3) shell became single crystalline and then the ZnO core melted. The average vanishing rate of the ZnO core was measured to be 4.2 nm s(-1). The thickness of the Al(2)O(3) nanotubes can be precisely controlled by the deposition process. Additionally, the inner geometry of nanotubes can be defined by the initial ZnO core. The result shows a promising method to obtain the biocompatible Al(2)O(3) nanotubes, which may be applied in drug delivery, biochemistry and resistive switching random access memory (ReRAM).
authors: Department of Materials Science and Engineering, National Chiao Tung University, No.1001, University Rd., East Dist., Hsinchu City 300, Taiwan.
authors: Chun-Wei
authors: CW
authors: Huang
authors: Cheng-Lun
authors: CL
authors: Hsin
authors: Chun-Wen
authors: CW
authors: Wang
authors: Fu-Hsuan
authors: FH
authors: Chu
authors: Chen-Yen
authors: CY
authors: Kao
authors: Jui-Yuan
authors: JY
authors: Chen
authors: Yu-Ting
authors: YT
authors: Huang
authors: Kuo-Chang
authors: KC
authors: Lu
authors: Wen-Wei
authors: WW
authors: Wu
authors: Lih-Juann
authors: LJ
authors: Chen