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Research paper : Basic materials research for the development of ubiquitous-energy devices (M. Kohyama et al.)−51−Synthesiology - English edition Vol.2 No.1 (2009) For the Au/CeO2 system, we discovered the novel phenomena that (i) Au nano-particles supported on CeO2 disappeared during TEM observation, as layer-by-layer with only the Au first layer at the interface remained, and that (ii) the Au nano-particles recovered at the same places when the electron beam was stopped and left in the chamber[19][20]. Such atmosphere-dependent structural changes should be related to the catalytic property, and the clarification of mechanism is important. It could be inferred that the effect of oxygen deficiency on CeO2 surfaces is important since the Au particle growth on CeO2 at high temperature could be controlled in the H2 atmosphere. We succeeded in obtaining a detailed image of the interface atomic arrangement for the first time using the HAADF-STEM method (Fig. 8)[21]. The interface is steep and the distance between the Au and Ce atomic layers can be measured. By comparing this observation with the first-principles calculation, it could be concluded that a Ce-terminated interface is formed. The series of phenomena could be explained from the theoretical analysis including the chemical potential depending on the atmosphere, where the Au-atom trapping by oxygen vacancies in CeO2 surfaces and bulk and the strong bonding at the Ce-terminate interface are involved.At this point, the mechanism of the catalytic activity of the Au/TiO2 and Au/CeO2 systems are not completely clarified, but there have been no other cases where the interface structures of metal/oxide hetero catalysts are revealed at this resolution, as proved by many awards (Table 1). From the first-principles calculated based on this observation, it is strongly implied that the key of function is held by the stoichiometry of the interface and its control by atmosphere. As next step, the TEM observation in gas atmosphere and the first-principles calculation of molecular absorption and reaction path of the real interface and peripheral models are in progress.The above results were made possible by effectively setting topics and plans through continuous collaboration and close information exchange with the catalyst production groups inside and outside the unit.4.4 Recent awardsThe above research activities have won several awards. Table 1 shows the recent awards. The results of basic material analysis through close collaboration with the material development have drawn much attention, and our activities have been acclaimed highly as basic science. The reasons for receiving the awards are as follows: (1) the construction of high level basic analysis technologies and new methods, (2) the pioneering work advancing the frontier of the clarification of the energy and environment materials and the metal/inorganic nano-hetero interfaces, and (3) the results of basic analysis highly expected to be used in real material development and improvement. Of course, rather than pure basic research, the awards were probably given to the results and expectations from the developmental viewpoint.5 Discussion and summaryIn general, there are still no solid methodology or guideline for the development of new materials, and this is a grave fact. From the perspective of device development (Type 2 Basic Research), various findings must be pursued (results of Type 1 Basic Research and experience from Type 2 Basic Research) and the development and search of the materials must be done by trial and error. However, since the process (of making the material in various ways) deals with nature (matter), we often run into novel mysterious phenomena that no one has experienced before. In seeking novel materials, this cannot be avoided. When that happens, we cannot wait for someone else to solve the issue for us (with Type 1 Basic Research). The developer and group of developers must attempt clarification by investigating the phenomena by themselves. Therefore, it is necessary to utilize the Type 1 Basic Research available within the same research organization and to closely collaborate with such researchers. This is the way of materials development as Full Research. On the other hand, to make such collaborative activity effective, the researchers involved in Type 1 Basic Research bear mission to work hard on analysis method and to pioneer and refine the new methods. For dramatic materials development, it is important to strike balance and efficiency of “specialized” and “collaborative” researches between the development (Type 2 Basic Research) and the analysis (Type 1 Basic Research).The experience of the Authors is limited, and not all issues are solved. Some areas are dependent on individual ability. The lessons and significance at this point can be summarized as follows. First, it is important to have an organization and management policy where the development and basic analysis groups can collaborate through daily information exchange on the same floor or at close proximity. Second, the priority topic in actual development often deals with new phenomenon or interdisciplinary phenomenon that are valuable in terms of basic science. Basic research in collaboration with actual development raises the level of basic research. Of course, the researchers must spend more effort to establish new analysis technology. Such efforts may lead to the creation of new disciplines (for example, electrochemistry and catalyst chemistry at the atomic and electronic level). Third, the cooperation of development and basic research provides plans and ideas for material design and development from new perspective to the development side. Of course, continuous efforts are necessary for such ideas to be truly utilized in dramatic development. Fourth, we believe the continuous accumulation and systemization of experience and knowledge in the collaboration of such materials development and basic research, as well as the education of human resources that are capable to handle them, is the “core competence” that must be carried on and developed in a research institution.

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