Zinc oxide (ZnO) is a reliable luminescence material which possesses potential applications in visible light emitting devices and biological fluorescence labeling. In this work, flower-like and sphere-like ZnO microstructures self-assembled by single-crystalline ZnO nanorods and nanoslices, respectively, have been successfully synthesized by an innovative solvothermal method using NaOH, Zn(NO3)(2)center dot 6H(2)O and zinc particles as raw materials. The results reveal that zinc particles have significant enhancement on the photoluminescent performance of ZnO nanostructures in the visible spectral region. Mechanisms of visible emission for ZnO have been discussed based on the origin of the defects. (C) 2014 Elsevier B.V. All rights reserved.