Research Abstract |
We at first constructed a vacuum apparatus in which we can prepare multiply twinned particles (MTP) by deposition. Using this apparatus we made MTP micelle as follows. NaCL of 1,500A were at first deposited on a spherical glass vessel which maintained at 350゚C.On this surface, we deposited Au of 100A and NaCL of 1000A alternately and MTPs were buried in the deposited NaCL film. A thiols solution (M beta-mercaptopropionic acid : HSCH_2CH_2COOH,10^<-3>mol/1) was poured into the glass vessel and MTP were covered by thiols molecules, resulting in the MTP micells. We called this moleculer assembly "uni-particles". A drop of the MTP micelle solution was put on a mesh of electron microscope, dried and observed by transmission electron microscope, electron diffraction and acanning electron microscope. Almost of the Au particles were MTPs with average diameter of about 70A.We observed a new phenomenon that when electron beam was concentrated on the sample, some of the MTP micelles started to move to approach in each other and they merged to one particle after 3-5 minutes. We analyzed the composition of the MTP micelles by total reflection angle X-ray spectroscopy (TRAXS) and detected Au and S signals and confirmed the MTP micelle structure. We studied the MTP micelle by electron spectroscopy (UPS,MIES), and obeseved that thiolate molecules of carboxyl acid are stretching toward outside of MTP.Furthermore, we studied the MTP micelle by nucler magnetic resonance (NMR) and confirmed the MTP micelle structure. We have pinted out that the apprication of the MTP micells to metal painting maaterial, column-chromatography, catalytic agent, electronic device, cosmetics etc.
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