I am interested in the mechanisms of mineral formation, and I have recently focused on visualizing changes in pH and ion concentration distributions during the dissolution and growth of minerals in aqueous solutions (Figure). Direct observation of local changes in the chemical environment around reacting minerals has revealed ion behaviors that differ from what would be predicted by conventional chemical equations. In this technique, reagents are used that emit different fluorescence intensities depending on ion concentration differences when irradiated with light of certain wavelengths. Originally developed for biological research, we have adapted and refined this method for application to inorganic reactions. We expect it will not only contribute to elucidating fundamental mineral reaction mechanisms but also enable a quantitative understanding of how these reactions influence environmental changes and aid in determining the reactivity of industrial materials.

I am joining the project named “Carbonate Biology (Project leader: Prof. Michio Suzuki of U Tokyo)”, which aims to clarify how the process by which marine organisms such as bivalves create calcium carbonate shells (biomineralization) contributes to carbon dioxide fixation in the global environment. Generally, the reaction forming calcium carbonate (calcification) has been recognized as a process that releases carbon dioxide and lowers pH, and thus does not contribute to carbon fixation. However, we believe that the movement of hydrogen ions may be controlled by organic matter during the biomineralization process, thereby fixing carbon dioxide. This is supported by the observations of pH changes during actual calcification. By elucidating this mechanism, we aim to contribute to a decarbonized society.

“Mineral” is generally referred to as a naturally occurring crystal, and mineralogy is connected to various fields related to crystals. After I got my degree in experimental and simulation research on mineral formation and stability, I pursued education and research on gemstones at a technical school and a private company. I later moved to the engineering department of a university, where I conducted simulation research on crystal growth for solar cells. Currently, I am also focusing on crystals formed by organisms, such as bivalves, foraminifera, teeth, and bones, and am advancing collaborative research with researchers in each field. Furthermore, the processes at the early stages of crystal formation have consistently been a subject of my interest, and the simulation study on the molecular aggregation processes, which was conducted with the quantum chemistry experts, is one of the subjects we want to further explore. My students’ research topics are diverse, and we enjoy our research, challenging new fields.