title: Growth and optical properties of faceted hexagonal ZnO nanotubes.
abstract: Well-faceted hexagonal ZnO nanotubes were synthesized by a simple hydrothermal method and the subsequent aging process without any catalysts or templates. The formation of the tubular structure is closely linked to the polarity of ZnO and the selective adsorption behavior of Zn2+ amino complexes. The surface-related optical properties were studied with use of Raman and photoluminescence spectra. It was found that the oxygen vacancy-related visible emission intensity decreased while surface defect-related visible emission intensity increased when the nanotubes were annealed in oxygen ambient. The anomalous enhancement of PL integrated intensity with the temperature shows fairly high surface state density existing in ZnO nanotubes.
authors.affiliation: Center for Advanced Opto-Electronic Functional Material Research, Northeast Normal University, Changchun 130024, People's Republic of China.
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Tong
authors.forename: Yichun
authors.initials: Y
authors.lastname: Liu
authors.forename: Changlu
authors.initials: C
authors.lastname: Shao
authors.forename: Yuxue
authors.initials: Y
authors.lastname: Liu
authors.forename: Changshan
authors.initials: C
authors.lastname: Xu
authors.forename: Jiying
authors.initials: J
authors.lastname: Zhang
authors.forename: Youming
authors.initials: Y
authors.lastname: Lu
authors.forename: Dezhen
authors.initials: D
authors.lastname: Shen
authors.forename: Xiwu
authors.initials: X
authors.lastname: Fan