Raman spectra of CuO nanocrystals

CuO nanoparticles were successfully prepared by a one-step solid-state reaction under ambient conditions. Three pellet samples with different grain sizes were obtained by annealing at high temperature. The room temperature Raman spectra of these samples show that as the grain size decreases, the Raman peaks shift to lower wavenumber and become broader owing to size effects. The dependences of the Raman spectra on the wavelength of the excitation laser and temperature were also investigated.