Surface-Enhanced Raman Scattering for ZnO Observed in Ag@ZnO Core-Shell Heterostructures

Core-shell Ag@ZnO heterostructures are designed and fabricated by a facile two-step chemical method. The heterostructures are composed of Ag microspheres as the core, on which plenty of small ZnO nanorods grow as the shell. The morphological, structural and Raman properties of the composites were investigated by means of powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman scattering spectra. A strong surface-enhanced Raman scattering (SERS) and Raman red shift of ZnO nanorods were observed in Ag@ZnO core-shell nanocomposites due to the effect of Ag microspheres.