Fig. 1 Phase map of temperature wave propagationFig. 1 Phase image of Cu-CHA zeolite observed from [100] direction. The scale bar is 5 Å. The arrow indicates Cu site with high possibility.75Beside figure shows a HAADF-STEM image and a time distribution image of temperature wave propagation acquired by nano-sized thermocouple attached to the specimen.Poster Award NomineePoster Award NomineeDirect Observation of Cu Sites in SCR Zeolite Catalysts Using Electron PtychographyP4-07Masahiko Shimizu1,2,3, Katsuaki Nakazawa2, Kazutaka Mitsuishi2, Hajime Matsumoto1,2, Hisashi Shima1, Takahiko Takewaki1, and Ayako Hashimoto2,31 Science & Innovation Center, Mitsubishi Chemical Corporation2 Research Center for Energy and Environmental Materials, National Institute for Materials Science (NIMS)3 Graduate School of Science and Technology, University of TsukubaSelective catalytic reduction (SCR) of NOx is the mainstream method for cleaning diesel exhaust gas, and Cu-doped zeolites are widely used as SCR catalysts. It is thought that the local coordination of the active species Cu ions contributes to the catalyst’s activity and degradation, but it has not yet been possible to analyze the structure at the atomic level. Therefore, in this study, we attempted direct observation using electron ptychography[1] to determine the Cu site and visualize the factors that cause hydrothermal degradation in SCR catalysts. Fig. 1 shows the phase image of Cu-CHA. In the poster, we will discuss the results of the observation of the structure of CHA zeolite after hydrothermal degradation, and the structural changes before and after hydrothermal test in AEI-type zeolite with hydrothermal durability. [1] K. Mitsuishi, et al., Sci. Rep., 13, 316 (2023).P4-08Phase Mapping of Temperature Waves in Submicron-structured Ceramics Using PSTAMHieu Duy Nguyen1, Isamu Yamada2, Toshiyuki Nishimura3, Hyunyong Cho1, Takao Mori4,5, Koji Kimoto1,and Naoyuki Kawamoto11 Center for Basic Research on Materials, National Institute for Materials Science (NIMS)2 Yamada R&D Support Enterprise3 Research Center for Structural Materials, National Institute for Materials Science (NIMS)4 International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS)5 Graduate School of Pure and Applied Sciences, University of TsukubaTemperature waves were induced inside submicron-structured ceramics such as AlN and WB4-B composite, using a pulsed convergent electron beam of a scanning transmission electron microscopy (STEM) mode inside a transmission electron microscope (TEM). Strong contrast of phase delays between grains and grain boundaries, and different phases gives an idea to qualitatively characterize thermal properties and heat route inside submicron/nano-structured ceramics. This result provides a possibility to solve thermal-related issues in various applications such as thermal management of electronic devices, and development of heat sink and thermoelectric materials.[1] Hieu Duy Nguyen, Naoyuki Kawamoto et al., Sci. Adv, 10, eadj3825 (2024).
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