A simple and efficient approach is developed for the synthesis of single crystal zinc oxide (ZnO) nanoparticles on multi-walled carbon nanotubes (MWNT). Moreover, the effect of heat treatment on ZnO-coated MWNT is investigated. The results reveal that the MWNT are decorated by ZnO particles. The MWNT are continuously coated by ZnO nanoparticles at 450 and 600 degrees C, and the average size of ZnO nanoparticles is about 11 and 48 nm, respectively. However, the coated layer of ZnO on the surface of MWNT becomes discontinuous when the temperature of heat treatment reaches 750 degrees C. The average size of ZnO particles at 750 degrees C is about 89 nm. Furthermore, the UV emission of MWNT is improved significantly through modification with ZnO. (c) 2006 Published by Elsevier Ltd on behalf of Acta Materialia Inc.