In this paper, I report novel magnetic functionalities such as humidity-induced magnetization, light-induced spin-crossover magnetic phenomenon, chiral photomagnetism, photoswitching of magnetization-induced second harmonic generation, and light-induced switching of superionic conductivity, using cyanide-bridged metal assemblies including Prussian blue analogues. Furthermore, by nanoscale chemical synthesis, novel functional materials were synthesized from abundant elements. For example, epsilon-iron oxide (ε-Fe2O3) shows a huge coercive field and high-frequency millimeter wave absorption [BBC, Science Museum London] and has potential for a novel recording method of focused millimeter wave assisted magnetic recording, F-MIMR [The Economist]. As another example, we have discovered lambda-trititanium-pentoxide (λ-Ti3O5), which exhibits photo-induced metal-semiconductor transition at room temperature as well as long-term heat storage properties suggesting a novel concept of preserving heat energy for a prolonged period [AFP, NHK]. Such metal oxide materials contribute to solving environmental and energy issues and to promoting green transformation (GX). Here, I will introduce the functional materials developed in our group. Additionally, I will also introduce the PhD project “Fostering Advanced Human Resources to Lead Green Transformation” supporting 600 PhD students of all fields at the University of Tokyo.

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Ohkoshi Laboratory:
www.chem.s.u-tokyo.ac.jp/users/ssphys/english/index.html
“Fostering Advanced Human Resources to Lead Green Transformation” Project:
www.cis-trans.jp/spring_gx/index-e.htm