Growth of dumbbell-like ZnO microcrystals under mild conditions and their photoluminescence properties.
Large-scale uniform dumbbell-like ZnO microcrystals were successfully synthesized via a facile solution method under mild conditions. The as-prepared dumbbells, with lengths of 3.5-5.4 microm and diameters of 1.3-1.8 microm, possess a single-crystal hexagonal structure and grow along the [0001] direction. The influence of the reactant concentration on the size and shapes of the ZnO samples had been studied, and the results revealed that the reactant concentration plays a crucial role in determining final morphologies of the samples. Moreover, the evolution process of the dumbbell-like ZnO microcrystals was viewed by field-emission scanning electron microscopy (FE-SEM) characterization, and a possible formation mechanism was proposed. In addition, optical properties of the ZnO samples prepared at different reaction times were also investigated by photoluminescence (PL) spectroscopy. The room-temperature PL spectrum of the dumbbell-like ZnO microcrystals shows a strong UV emission peak. The UV emission is further identified to originate from the radiative free-exciton recombination by the temperature-dependent PL.
Yu
Qingjiang
Q
National Laboratory of Superhard Materials, Jilin University, Changchun, 130012, P. R. China.
Yu
Cuiling
C
Yang
Haibin
H
Fu
Wuyou
W
Chang
Lianxia
L
Xu
Jing
J
Wei
Ronghui
R
Li
Hongdong
H
Zhu
Hongyang
H
Li
Minghui
M
Zou
Guangtian
G
Wang
Guorui
G
Shao
Changlu
C
Liu
Yichun
Y