T.X. Phuoc, D. Mcintyre, X. Song, M.K. Chyu
It has been known that catalytic and sensing properties of semiconductor and metal nanoparticles (NPs) can be greatly enhanced if they are made in the form of nanocomposites. For that reason, in this work, we will report the synthesis and characterization of Au/Cu2O nanocomposites using multiple laser ablation steps. Pure Au and Cu2O NPs were separately produced by nanosecond pulse laser ablation of pure gold and pure copper targets in deionized water containing 0.1% chitosan by weight. The prepared colloids were mixed, heated, and stirred for about 24 hrs before they were ablated again. The heating and stirring step is necessary for Au and Cu2O nanoparticles to collide and agglomerate together. Our preliminary TEM analysis indicated that Au/Cu2O nanocomposites of 4 to 6 nm were formed with gold NPs that were melted and fused onto the Cu2O NPs. The UV–vis spectra of the prepared nanocomposites showed that the plasmon resonance absorption line shape was broadened and its peak was significantly red shifted with respect to pure Au NPs and slightly blue shifted with respect to pure Cu2O nanoparticles. Further analysis on the composite morphology, reactivity, and stoichiometry are being conducted and the results will be presented at the meeting.