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Research paper : Basic materials research for the development of ubiquitous-energy devices (M. Kohyama et al.)−46−Synthesiology - English edition Vol.2 No.1 (2009) From the perspective of material development, it is extremely important to experimentally and theoretically clarify structure, function, and various phenomena of such energy and environment materials using TEM observation and first-principles calculation[3]-[5]. For example, when a material with excellent function is discovered, further improvement, discovery, and development do not follow unless we understand why such excellent function manifests. Particularly, when the correlation between the structure and function of nanostructure is clarified, the possibility of developing excellent materials through design and control of nanostructures broadens dramatically. Also, the performance of functional materials deteriorate after they are used for some time, but measures against deterioration and plans for improvements cannot be made unless we understand what is occurring on the microscopic level. Rather than searching blindly for materials from experience and inspiration, it is much more efficient to search systematically upon understanding the crystal, electronic, and nano structures of the materials. Of course, there are ample examples of serendipity in material development. However, to run into serendipity efficiently or to not miss serendipity, it is essential to simultaneously conduct microscopic analyses.On the other hand, basic analysis of energy and environment materials has its unique problems. Manifestation of function involves complex reaction process and material transfer of hydrogen (proton) and Li-ions, such as absorption and reaction, electron transfer, oxidation/reduction, and valence fluctuation under gas atmosphere or in electric field. TEM observation is normally conducted under ultrahigh vacuum, and TEM observation of light element such as hydrogen and lithium is not generally easy. First-principles calculation at this point cannot readily handle large-scale reaction system or material and electron transfer. To advance the basic analysis of energy and environment materials, improvements and innovations of the basic analysis method itself is necessary. These are the factors that have delayed the application of basic analysis compared to other materials (such as semiconductor devices).3 Issues in the collaboration between material development and basic material analysisThere is a mountain of issues that must be clarified through application of basic analysis in the actual practice of R&D of ubiquitous energy device and its functional materials. However, there are several issues and difficulties to realize an efficient and useful collaboration. First, the pace and phase of material development and basic analysis are not necessary in synch. Since basic analysis involves the development of analysis method, it is often necessary to study one topic over long period. Naturally, the topics are studied separately, and flexible collaboration is inhibited. Second, since the actual materials and phenomena are often too complex, application of basic analysis is not easy. Therefore it becomes necessary to deal with the model material rather than the actual material, and close communication between the people involved in material development and those in basic analysis becomes necessary. Third, the gap in objectives and values, the difference in knowledge and understanding of the issue, and the lack of understanding of each other’s research occur between the researchers of material development and basic analysis, and this inhibits close collaboration.In the Research Institute for Ubiquitous Energy Devices (established in 2004) of AIST Kansai, a group was formed by researchers who were involved in TEM, SPM, and first-principles calculation since the inception of the Special Division of Green Life Technology in 2001. The group has engaged in discussion of where to position the basic material analysis in the system of Full Research and ways to contribute to material development. The reasons are: first, as mentioned earlier, energy and environment materials have potential for dramatic development through design and control provided by basic analysis since nanostructure itself is key to phenomena and functions; and second, we believe there is a creative value in the research methodology for the collaborative effort between basic analysis and development. Of course, as third reason, such collaborative effort is advantageous in obtaining research fund to maintain large apparatus.Figure 1 is an outline of the collaborative effort from the standpoint of basic analysis. First, for research unit management, we promoted (1) the sharing of objectives between development and basic analysis, and (2) the construction of system where flexible sharing and close communication were possible. These were promoted by holding colloquiums for the whole unit and working groups as well as discussion between unit leaders and groups, and budgetary allowances were provided to promote such activities. The Authors’ basic analysis group discussed the role of basic analysis as part of Full Research, and defined (1) the clarification and search to overcome the valley of death, and (2) the discovery and generalization/systematization of the potentials. It can be said that both aspects are necessary including the promotion of specific collaboration with development and the continuous effort for systemization by basic analysis. For the latter, we set the objectives of construction and systemization of theories of “metal/inorganic nano-hetero interfaces” that often held the key of function in ubiquitous energy devices[3]. In the metal-oxide hetero catalyst, exemplified by gold catalysts that will be mentioned later, and the Pt/C catalysts of proton-exchange fuel cells, hetero effect of the interface and the nano-size effect of metal particles are greatly involved in excellent function, but the details are unclear, and there is potential for building generalized design theory and guideline through the construction and systemization of theories. While tackling various topics flexibly from the perspective of (1), the findings

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