Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (7): 1421-1429.doi: 10.3866/PKU.WHXB201504221

• PHYSICAL CHEMISTRY OF MATERIALS • Previous Articles     Next Articles

Controlled Aspect Ratio Modulation of ZnO Nanorods via Indium Doping

HU Hai-Feng1,2, HE Tao1   

  1. 1 CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, P. R. China;
    2 University of Chinese Academy of Sciences, Beijing 100049, P. R. China
  • Received:2014-12-08 Revised:2015-04-21 Published:2015-07-08
  • Contact: HE Tao E-mail:het@nanoctr.cn
  • Supported by:

    The project was supported by the National Key Basic Research Program of China (973) (2011CB933200) and Ministry of Science and Technology of China (2015DFG62610).

Abstract:

In-doped ZnO nanorods (NRs) were synthesized by hydrothermal method. The X-ray diffraction (XRD) patterns showed that the ZnO lattices expanded upon In doping. According to the scanning electron microscopy (SEM) images, the aspect ratio (length- to- width ratio) of the ZnO NRs decreased as the concentration of In(III) in the precursor solution increased from 0% to 1.0% (atomic fraction, x), and increased with further increases in the In(III) concentration from 1.0%to 5.0%. The nonlinear modulation of the aspect ratio of ZnO NRs is believed to be due to the competition between the subst itutional doping of In3+ (InZn) and formation of InOOH intermediate, both of which are closely related to the behavior of In(OH)4-. In(OH)4- can be adsorbed onto zinc polar plane, and thus inhibits adsorption of Zn(OH)42- growth units. Furthermore, In(OH)4- can convert into InOOH, which can act as a crystal binder and enhance growth along the (002) plane. InZn can disrupt the zinc polar plane, resulting in the suppression of growth along the (002) facet. Therefore, the aspect ratio of ZnO NRs can be controllably modulated by changing the In concentration in the precursor solution. The current study furthers our understanding of the growth mechanism of In-doped ZnO, and presents a feasible method to prepare doped-ZnO NRs for real applications.

Key words: ZnO, In-doping, Hydrothermal method, Aspect ratio, Growth model

MSC2000: 

  • O649