東京大学 · Materials Science
히로시 시부카와 교수의 연구실은 주로 유기 루미네센트 라디칼, 금속-유기 프레임워크(MOF), 그리고 2차원 금속-리간드 나노시트를 중심으로 광학적·전기적 성질을 가진 신소재를 설계하고 합성합니다. 특히 안정적인 유기 자유 라디칼의 광학적 특성, 다기능성 금속-유기 나노구조물의 에너지 저장 및 전기화학적 거동, 그리고 표면 반응을 통한 정밀한 나노시트 합성이 핵심 연구 방향입니다. 다양한 분석 기법과 이론 계산을 융합한 다학제적 접근을 통해 기초 물성과 응용 가능성을 동시에 탐색하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
A luminescent open-shell organic radical with high chemical stability was synthesized. (3,5-Dichloro-4-pyridyl)bis(2,4,6-trichlorophenyl)methyl radical (PyBTM) was photoluminescent under various conditions. Fluorescence quantum yields of 0.03, 0.26, and 0.81 (the highest value reported for a stable organic radical) were obtained in chloroform, in poly(methyl methacrylate) film at room temperature, and in an EPA matrix (diethyl ether:isopentane:ethanol) at 77 K, respectively. The photostability o
The metallically conductive bis(diimino)nickel framework (NiDI), an emerging class of metal-organic framework (MOF) analogues consisting of two-dimensional (2D) coordination networks, was found to have an energy storage principle that uses both cation and anion insertion. This principle gives high energy led by a multielectron transfer reaction: Its specific capacity is one of the highest among MOF-based cathode materials in rechargeable energy storage devices, with stable cycling performance up
A π-conjugated coordination nanosheet comprising bis(aminothiolato)nickel (<b>NiAT</b>) moieties was synthesized by the reaction of Ni(acac)<sub>2</sub> with 1,3,5-triaminobenzene-2,4,6-trithiol at liquid-liquid and gas-liquid interfaces. The sheet thickness could be controlled down to a single layer (0.6 nm). Selected area electron diffraction and grazing incidence X-ray diffraction analyses indicated the formation of a flat crystalline sheet with a kagome lattice stacked in a staggered alignme
We investigated the emission properties of a photostable luminescent organic radical, (3,5-dichloro-4-pyridyl)bis(2,4,6-trichlorophenyl)methyl radical (PyBTM), doped into host molecular crystals. The 0.05 wt %-doped crystals displayed luminescence attributed to a PyBTM monomer with a room-temperature emission quantum yield of 89 %, which is exceptionally high among organic radicals. The 10 wt %-doped crystals exhibited both PyBTM monomer and excimer-centered emission bands, and the intensity rat
Abstract Recent studies on the azo-group-combined photochromic metal complexes are reviewed. These studies show unique trans–cis isomerization behaviors that have not been observed in regular organic azobenzenes. In the case of azobenzene-bound bis(terpyridine) complexes of transition metals, photoisomerization behavior depends strongly on the central metals, counterions, and solvents. Rh and Co complexes undergo photoisomerization smoothly, but the isomerization of Ru and Fe complexes is substa
The synthesis of palladium bis(dithiolene) complex nanosheets (PdDt) possessing a kagome-type lattice structure was performed via interfacial reaction between metal salt in aqueous phase and dithiolato ligand in organic phase. The PdDt nanosheets were characterised by AFM, STM, TEM revealing flat and sheet-like morphology; IR, UV spectroscopy show the corresponding coordination connectivity between metal and ligand, followed by powder X-ray diffraction and SAED, which determined nanosheets to be
Luminescent monoradicals are expected to show unique properties based on their doublet state, where establishing a method to improve their photostability is an important issue for expanding their photofunctionality. We synthesized a highly photostable luminescent organic radical, the bis(3,5-dichloro-4-pyridyl)(2,4,6-trichlorophenyl)methyl radical (bisPyTM), containing two pyridyl groups on a tris(2,4,6-trichlorophenyl)methyl radical (TTM) skeleton. bisPyTM in dichloromethane exhibited fluoresce
The use of organic radicals as building blocks is an effective approach to the production of open-shell coordination polymers (CPs). Two-dimensional (2D) CPs with honeycomb spin-lattices have attracted attention because of the unique electronic structures and physical properties afforded by their structural topology. However, radical-based CPs with honeycomb spin-lattices tend to have low chemical stability or poor crystallinity, and thus novel systems with high crystallinity and persistence are
We herein describe the development of an efficient enantioselective catalytic system that promotes the arylation of secondary silanes. Our method involves treatment of secondary silanes and aryl iodides with a Pd(2)(dba)(3)-asymmetric phosphoramidite ligand system to afford optically active tertiary silanes with good enantioselectivities.
