Effect of laser fluence on the size of copper oxide nanoparticles produced by the ablation of Cu target in double distilled water

Copper oxide nanoparticles produced in double distilled water at room temperature by laser ablation of the Cu target have been investigated using TEM, SEM, AFM, X-ray diffraction, photo-spectrometry and PIXE. Q-switched Nd:YAG laser operating at 1064 nm with a pulse duration of 5-6 ns was used to conduct the experiments in the fluence range of 5.73-9.87 J/cm(2). In each experiment, 12,000 laser pulses were used to ablate the target placed in double distilled water. Different diagnostic techniques reveal that the nanoparticles have a size between 2-55 nm and their mean size as well as the width of particle distribution increases with the laser fluence. Since no surface active material (surfactant) was added to water, the nanoparticles aggregated and settled down at the bottom of the container within a week. In addition to stable Cu2O, the XRD spectrum also shows the presence of suboxide Cu64O in the colloidal solution of nanoparticles produced in the present study.