NanoparticlesCore@Shell, Au@TiOx Nanoparticles by Gas Phase Synthesis
The gas phase synthesis and characterization of multifunctional core@shell, Au@TiOx nanoparticles is reported. The nanoparticles are produced in a one-step process by using a Multiple Ion Cluster Source under controlled environment that guaranties the purity of the nanoparticles. The growth of the Au cores (6 nm diameter) is stopped when these latter pass through the Ti plasma where they are covered by an ultra-thin (1 nm thick) and homogeneous titanium shell that is oxidized in-flight before the soft-landing of the nanoparticles. The Au cores are found to be highly crystalline with icosahedral (44%) and decahedral (66%) structures while the shell mainly composed by TiO2 (79%) is not ordered. The highly electrical insulating behaviour of the titanium oxide shell is evidenced by charging effect produced during x-ray photoemission spectroscopy.