title: Hexagonal crown-capped zinc oxide micro rods: hydrothermal growth and formation mechanism.
abstract: Hexagonal crown-capped ZnO micro rods were successfully prepared by a facile low-temperature hydrothermal method. The as-prepared ZnO micro rods are 4.4-5.2 μm in length and 2.4-3.6 μm in diameter, possessing a single-crystal hexagonal structure. The morphology evolution and structure changes were tracked during hydrothermal growth by field-emission scanning electron microscopy and X-ray diffraction, respectively. A three-stage growth mechanism of the hexagonal crown-capped ZnO micro rods was proposed and further verified by a growth solution renewal experiment. The room-temperature photoluminescence (PL) spectrum of the hexagonal crowns exhibits a strong UV emission at about 382 nm. The temperature dependent PL results indicate that the UV emission originates from the radiative free-exciton recombination.
authors: Department of Chemistry, State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084, China.
authors: Lijing
authors: L
authors: Zhang
authors: Xiaomiao
authors: X
authors: Liu
authors: Chong
authors: C
authors: Geng
authors: Huajing
authors: H
authors: Fang
authors: Zhipeng
authors: Z
authors: Lian
authors: Xiaoqing
authors: X
authors: Wang
authors: Dezhong
authors: D
authors: Shen
authors: Qingfeng
authors: Q
authors: Yan