Synthesis And Characterization Studies Of Porous Gold Materials

Porous metal materials on the one hand, can be used as structure materials with high porosity, low density and large specific surface characteristics; On the other hand can be used as functional materials with damped vibration, sound-absorbing, sound insulation,heat dissipation flame retardant and electromagnetic shielding performances. In this paper,the method of removing template by chemical soaking was used to make porous gold. And its characterizations have studied. The main contents and innovative achievements are as follows:(1) The dispersion polymerization method was used to make polystyrene spheres in micron size at first. Than the improved method of seed-growth was used to make core-shell composite microspheres of polystyrene micron spheres coated with gold. The method of removing template by chemical soaking was used to make porous gold at last.The scanning electron microscope( SEM) was used to observe the morphology and structure of core-shell composite micron spheres. The result was found that the golden spherical shell formed gold nanoparticles is dense and uniform and the thickness of golden spherical shell can be controlled at the minimum about 30 nm. The SEM was also used to observe the morphology and structure of the Porous Gold samples. The result was found that the porous structure of the sample is significant and the structure of pore is micron spherical.The result was that the sample is mainly composed of three elements of gold( Au), carbon( C) and oxygen( O) by test of X-ray photo-electron spectroscopy( XPS)and X-ray spectroscopy( EDAX) analysis.(2) The characterization of Porous Gold samples was studied. Results show that the sample is face-centered cubic lattice structure, the Au(111) crystal plane spacing is around0.24 nm. By the test of SAED, we find the hexagonal structure of graphene in diffraction spots. By the test of Raman, we observed that the change of Raman curve by oxidation offunctional groups and superposition of gold nanoparticles on the surface plasma resonance,reflects the continuous level of phase change the structure of the sample. Based on the analysis of above the inference is that there exist multilayer structure of oxidized graphene in samples. By UV-visible spectroscopy( UV-vis) test, we observed that the Au surface plasma resonance is of blueshift to about 485 nm wavelength in the absorption spectrum and resonance absorption near ultraviolet caused by oxidative functional groups.