RESEARCH

Microstructure and local chemical composition analysis using scanning electron microscopy and transmission electron microscopy is an indispensable analytical method for searching for new materials and for research and development of highly functional materials, and is routinely used in the fields of science, technology, and medicine. In particular, the “in-situ observation” method, in which the microstructure and functional/mechanical properties of a material are observed in real time by applying heat, light, or external force to the material, is a method that makes the most of the characteristics of the electron microscope, which allows us to see phenomena with our own eyes. Using this technique, it is possible to directly observe the functional properties of new materials such as graphene and carbon nanotubes, the mechanical properties of structural metals and ceramics, the compositional deformation behavior of rocks that leads to the mechanism of earthquakes, and the vibration modes of polymers at the nanometer scale. Our research group has a research level comparable to the world’s top groups, especially in in-situ observation using transmission electron microscopy. In the U.S. and Europe, the development of operando electron microscopy, which enables the exploration of unknown materials and the evaluation of their functional properties, is now being actively pursued by further evolving the in-situ observation method and integrating it with data science and computational science methods. This is expected to bring about a dramatic change in materials analysis, as well as in the research and development of substances and materials, similar to the change from a five-year-old cell phone to a state-of-the-art smartphone. Our research group routinely collaborates with Professor Satoshi Hata’s group at the Graduate School of Science and Engineering and the Center for Ultramicroscopy at the Ito Campus to establish next-generation microscopic analysis methods, such as Operando electron microscopy, and to elucidate physical and chemical phenomena using these methods. At the same time, we are conducting research and education to acquire the fundamentals for understanding the “correlation between microstructure and functional/mechanical properties,” which is indispensable for the next generation of physics and materials research through these advanced projects.

As the pursuit of a sustainable society has become a central theme in social and industrial activities, and as reflected in the United Nations’ 17 Sustainable Development Goals (SDGs), there is a growing awareness of global issues that transcend national and regional boundaries. At the same time, nanomaterials and nanostructures—produced through nanotechnology and now embedded in our daily lives through products such as disinfectants, deodorizing agents, and 3D printers—interact with various natural and anthropogenic nanoparticles in the environment. How do these interactions take place, and what effects do they have on the Earth system?

After use, do engineered nanomaterials conveniently decompose into atoms and simply disappear? While the concept of infinite dilution no longer holds even on a global scale, many questions remain regarding the planetary-scale circulation of nanomaterials. From the perspectives of materials science and Earth and environmental sciences, particularly in research institutions in the United States, this talk examines how advanced analytical techniques can capture and characterize nanomaterials as environmental factors, introducing representative case studies.