The mixtures of Cu nanoparticles and ZnO nanoparticles were obtained with some physical methods, such as grinding and ultrasionic dispersion and characterized by EPR and XPS. The EPR results showed that no signal could be observed in the Cu EPR spectrum and only a signal g =1.961 appeared in the ZnO spectrum before they were mixed. After they were mixed, a special signal that could be attributed to Cu 2+ was observed in the spectrum. The XPS results showed that the values of the kinetic energy of ZnL 3M 45 M 45 and O 1s changed in the XPS spectrum of the mixture, indicating that Zn valance decreased. We could also find that a new O species appeared in the mixture. These results showed that there was some interaction between Cu nanoparticles and ZnO nanoparticle, and the model would be Cu—O—Zn.
