Sulfur-doped zinc oxide (ZnO) Nanostars: Synthesis and simulation of growth mechanism
ZnO nanostar, hexagram, thiourea, sulfur doping, growth mechanism, ab initio simulation
We present a bottom-up synthesis, spectroscopic characterization, and ab initio simulations of star-shaped hexagonal zinc oxide (ZnO) nanowires. The ZnO nanostructures were synthesized by a low-temperature hydrothermal growth method. The cross-section of the ZnO nanowires transformed from a hexagon to a hexagram when sulfur dopants from thiourea [SC(NH2)2] were added into the growth solution, but no transformation occurred when urea (OC(NH2)2) was added. Comparison of the X-ray photoemission and photoluminescence spectra of undoped and sulfur-doped ZnO confirmed that sulfur is responsible for the novel morphology. Large-scale theoretical calculations were conducted to understand the role of sulfur doping in the growth process. The ab initio simulations demonstrated that the addition of sulfur causes a local change in charge distribution that is stronger at the vertices than at the edges, leading to the observed transformation from hexagon to hexagram nanostructures.
Tsinghua University Press
Jinhyun Cho,Qiubao Lin,Sungwoo Yang,Jay G. Simmons,Yingwen Cheng,Erica Lin,Jianqiu Yang,John V. Foreman,Henry O. Everitt,Weitao Yang,Jungsang Kim,Jie Liu, Sulfur-doped zinc oxide (ZnO) Nanostars: Synthesis and simulation of growth mechanism. NanoRes.2012, 5(1): 20–26