Nanoscale Element Replacement Science: Structural Transformation of Nanocrystalline Phases and Development of Novel Functions

2023 Fiscal Year Final Research Report

• Project/Area Number: 19H05634
• Research Category: Grant-in-Aid for Scientific Research (S)
• Allocation Type: Single-year Grants
• Review Section: Broad Section E
• Research Institution: Kyoto University
• Principal Investigator: Teranishi Toshiharu 京都大学, 化学研究所, 教授 (50262598)
• Project Period (FY): 2019-06-26 – 2024-03-31
• Keywords: ナノ材料 / 元素置換 / 金属化合物 / 合金 / イオン結晶 / 電子構造 / 触媒

Outline of Final Research Achievements

A variety of unprecedented alloy nanoparticles have been successfully synthesized by galvanic replacement reactions of nanoparticles in which p-block elements have been introduced into d-block metal nanoparticles, and in manifesting novel plasmonic properties. By utilizing the interelement miscibility, unprecedented Z3-type nanoparticles have been synthesized for the first time. On the other hand, considering the characteristic that the anion sublattice is maintained in the cation exchange reaction of ionic nanoparticles, thermodynamically metastable spinel-type Ni3Se4 nanoparticles and Cu2-xSe/Ni3Se4 heterostructure nanoparticles have been successfully obtained by cation exchange between Cu2-xSe nanoparticles and Ni(II). Furthermore, in the cation exchange reaction of hexagonal Cu1.8S nanoparticles, we have clarified the factors that determine the crystal structure of the nanoparticles after cation exchange.

Free Research Field

無機合成化学

Academic Significance and Societal Importance of the Research Achievements

11族元素を含まない合金ナノ粒子において、可視プラズモン特性を示すことを実証し、その原理を解明した。また、特定の元素間相溶性を考慮することで、前例のない合金構造を安定化することを実証し、未踏合金結晶構造群の合成指針を示すことができた。一方、イオン結晶ナノ粒子のカチオン交換反応において、熱力学的準安定相を安定化することができることを実証したのみならず、カチオン交換後のナノ粒子の結晶構造決定因子を明らかにした。これらの材料は、新たな可視プラズモン材料や各種触媒（水分解触媒、酸素還元触媒など）として高いポテンシャルを有していることを示した。