No 3, Vol. 10, 2005, pages 277-282


S. Yagi, T. Nomoto, G. Kutluk, H. Sumida, H. Namatame, M. Taniguchi and K. Soda


The noble metal membrane with nanosize hole structure is synthesized by rhodium nanoparticle, which are protected by poly-vinylpyrrolidone (PVP) as surfactant. There are many nanoholes on the Rh(PVP) membrane surface. We have measured the nanohole sizes by means of AFM (Atomic Force Microscope) with tapping measurement mode. The distributions of the nanoholes are from 30 nm to 400 nm in diameter. We have investigated the temperature dependent adsorption behavior of dimethylsulfide [(CH3)2S] on the Rh(PVP) membrane surface by sulfur K-edge NEXAFS (Near-Edge X-ray Absorption Fine Structure) and XPS (X-ray Photoelectron Spectroscopy) measurements. It is found that this surface has a high reactivity at 80K for the desulfurization of the sulfur-including molecule. At all substrate temperature region from 80 to 600K, a very large peak is observed at around 2482 eV in sulfur K-edge NEXAFS spectra. This result means DMS molecules stably adsorb with the membrane surface oxygen and form SO42- structure.

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