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Schlagwörter:
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Zusammenfassung:
In this paper, we report on the first successful attempt of chemical vapor deposition (CVD) synthesis of
well-aligned single-crystalline ZnO nanotube arrays on Mo wire mesh. According to detailed morphology
and composition analyses, a rational growth model is proposed to illustrate the growth process of the hollow ZnO nanotubes. Metastable Zn-rich ZnOx
nanorods formed in the early stage are believed to play a vital role towards the formation of nanotube configuration. In addition, we also successfully fabricate ZnO/
ZnS and ZnO/CdS core/shell nanotube arrays by simply depositing ZnS and CdS on the pre-fabricated ZnO
nanotubes. Despite the existence of a large lattice mismatch, the grown ZnS and CdS layers are somewhat
single-crystalline and show an epitaxial orientation relationship with the inner ZnO, that is, [0001]ZnS or CdS//[0001]ZnO and
(10-10)ZnS or CdS//(10-10)ZnO. Further, room temperature cathodoluminescence (CL)
characterization indicates that after surface decoration, the formed ZnO-based heterostructures show dis-
tinguished optical properties. Quenching of 67.2% and 99.7% of ZnO near-band-gap (NBE) emission is ob-
served on ZnO/CdS and ZnO/ZnS, respectively. Efficient charge separation resulting from type-II band con-
figuration is considered to be responsible for the variation of optical properties. Our method may represent
a powerful synthesis platform for creation of ZnO nanotubes and ZnO-based hollow heterostructures with
tunable properties.
