A Versatile Approach to the Fabrication of Palladium Hollow Spheres with Aluminiumoxide Nanoparticles as Template

Palladium hollow nanospheres were prepared by the adsorption of metal nanoparticles onto functionalized gamma-Al2O3 templates. The silanizing agent 3-mercaptopropyl trimethoxysilane was reacted with the surface of the gamma-Al2O3 templates to afford thiol-terminal groups. Metal layers of palladium were coated directly on the gamma-Al2O3 templates by increasing the temperature stepwise. Then, the dissolution of the gamma-Al2O3 template using 40 wt% HF solution enabled the formation of self-organized metallic palladium hollow nanospheres. The palladium hollow nanospheres were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and fourier-transform infrared spectroscopy (FTIR) techniques.