Journal of Nanoparticle Research

, Volume 13, Issue 7, pp 2875–2886

ZnO–ZnS heterostructures with enhanced optical and photocatalytic properties

Research Paper

DOI: 10.1007/s11051-010-0176-z

Cite this article as:
Wu, D., Jiang, Y., Yuan, Y. et al. J Nanopart Res (2011) 13: 2875. doi:10.1007/s11051-010-0176-z

Abstract

ZnO–ZnS heterostructures were fabricated via using ZnO rods as template in different Na2S aqueous solutions. These heterostructures are 5–6 μm in length and formed by coating ZnO rod with a layer of porous ZnS shell comprising primary crystals about 10 nm in diameter. Subsequently, intact ZnS polycrystalline tubes were obtained by removing the ZnO cores with 25% (wt) ammonia. The as-prepared products were characterized by scanning electronic microscopy (SEM), transmission electronic microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX), Fourier transform infrared (FT-IR), and electrochemical impedance spectroscopy (EIS). It was found that the electron transfer between ZnS shell and ZnO core strongly affect the photoluminescence and photocatalytic performances of these heterostructures. The rapid transfer of photo-induced electrons from the ZnS shell to the ZnO core leads to enhanced ultraviolet emission. However, if this correlation was destroyed, then the corresponding heterostructure exhibits improved photocatalytic efficiency due to the reduced volume recombination of the charge carries and the multiple reflection effect. Finally, a model based on band-gap alignment was proposed to elucidate the underlying mechanism of the enhanced UV emission and photocatalytic activity of these unique heterostructures.

Keywords

SemiconductorHeterostructureCrystal growthPhotoluminescencePhotocatalysis

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.College of Chemistry and Environmental ScienceHenan Normal UniversityXinxiangChina
  2. 2.Department of Materials Science and Chemical EngineeringSchool of Chemical Engineering, Dalian University of TechnologyDalianChina