α相PdHxにおけるPd-H相互作用に関する系統的研究

京都大学0048新制・課程博士博士(理学)甲第21442号理博第4435号新制||理||1637(附属図書館)京都大学大学院理学研究科化学専攻(主査)教授 北川 宏, 教授 竹腰 清乃理, 教授 吉村 一良学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDGA

MOP x MOF: Collaborative Combination of Metal-Organic Polyhedra and Metal Organic Framework for Proton Conductivity

We report a hybrid solid system, UMOM-100-a and UMOM-100-b, synthesized by incorporation of Cu-based metal-organic polyhedra (MOPs) into a porous metal-organic framework (MOF) host, PCN-777. The MOP guests have acid (S03-) functional groups, acting as functionalized nanocages, whereas the porosity is still maintained for proton conductivity. The key parameter for the UMOM-100 series is the number of MOPs inside a MOF, which controls the ratio between meso- and micropores, polarity, and finally proton conductivity. This is an example demonstrating a new design strategy for porous solids to add active components into porous MOFs, opening up possibilities in other applications such as solid-state electrolytes and heterogeneous catalysts

Defect Control To Enhance Proton Conductivity in a Metal–Organic Framework

Defect Control To Enhance Proton Conductivity in a Metal–Organic Framewor

Nonpolar-to-Polar Phase Transition of a Chiral Ionic Plastic Crystal and Switch of the Rotation Symmetry

The synthesis of a new ionic plastic crystal, tetra­ethyl­ammonium-<i>d</i>₂₀ d-10-camphor­sulfonate, is reported. The crystal has three solid phases, the structures of which were determined by single-crystal X-ray diffraction (XRD). XRD analysis revealed a phase transition from nonpolar space group <i>P</i>2₁2₁2 to polar space group <i>P</i>2₁ with increasing temperature. The dynamics of the d-10-camphor­sulfonate anion and the tetra­ethyl­ammonium-<i>d</i>₂₀ cation was investigated by variable-temperature ¹H and ²H solid-state NMR spectroscopy. The anion showed swing motion in high-temperature phases, which is in good agreement with the disorder observed in XRD analysis. The cation showed uniaxial rotation even in the low-temperature phase. The rotation axis of the tetrahedral structure showed a transition from the two-fold axis to the three-fold axis with the phase transition

The Role of a Three Dimensionally Ordered Defect Sublattice on the Acidity of a Sulfonated Metal–Organic Framework

Understanding the role that crystal imperfections or defects play on the physical properties of a solid material is important for any application. In this report, the highly unique crystal structure of the metal–organic framework (MOF) zirconium 2-sulfoterephthalate is presented. This MOF contains a large number of partially occupied ligand and metal cluster sites which directly affect the physical properties of the material. The partially occupied ligand positions give rise to a continuum of pore sizes within this highly porous MOF, supported by N₂ gas sorption and micropore analysis. Furthermore, this MOF is lined with sulfonic acid groups, implying a high proton concentration in the pore, but defective zirconium clusters are found to be effective proton trapping sites, which was investigated by a combination of AC impedance analysis to measure the proton conductivity and DFT calculations to determine the solvation energies of the protons in the pore. Based on the calculations, methods to control the p<i>K</i>_a of the clusters and improve the conductivity by saturating the zirconium clusters with strong acids were utilized, and a 5-fold increase in proton conductivity was achieved using these methods. High proton conductivity of 5.62 × 10^–3 S cm^–1 at 95% relative humidity and 65 °C could be achieved, with little change down to 40% relative humidity at room temperature

Nonpolar-to-Polar Phase Transition of a Chiral Ionic Plastic Crystal and Switch of the Rotation Symmetry

The synthesis of a new ionic plastic crystal, tetra­ethyl­ammonium-<i>d</i>₂₀ d-10-camphor­sulfonate, is reported. The crystal has three solid phases, the structures of which were determined by single-crystal X-ray diffraction (XRD). XRD analysis revealed a phase transition from nonpolar space group <i>P</i>2₁2₁2 to polar space group <i>P</i>2₁ with increasing temperature. The dynamics of the d-10-camphor­sulfonate anion and the tetra­ethyl­ammonium-<i>d</i>₂₀ cation was investigated by variable-temperature ¹H and ²H solid-state NMR spectroscopy. The anion showed swing motion in high-temperature phases, which is in good agreement with the disorder observed in XRD analysis. The cation showed uniaxial rotation even in the low-temperature phase. The rotation axis of the tetrahedral structure showed a transition from the two-fold axis to the three-fold axis with the phase transition

Nonpolar-to-Polar Phase Transition of a Chiral Ionic Plastic Crystal and Switch of the Rotation Symmetry

The synthesis of a new ionic plastic crystal, tetra­ethyl­ammonium-<i>d</i>₂₀ d-10-camphor­sulfonate, is reported. The crystal has three solid phases, the structures of which were determined by single-crystal X-ray diffraction (XRD). XRD analysis revealed a phase transition from nonpolar space group <i>P</i>2₁2₁2 to polar space group <i>P</i>2₁ with increasing temperature. The dynamics of the d-10-camphor­sulfonate anion and the tetra­ethyl­ammonium-<i>d</i>₂₀ cation was investigated by variable-temperature ¹H and ²H solid-state NMR spectroscopy. The anion showed swing motion in high-temperature phases, which is in good agreement with the disorder observed in XRD analysis. The cation showed uniaxial rotation even in the low-temperature phase. The rotation axis of the tetrahedral structure showed a transition from the two-fold axis to the three-fold axis with the phase transition

Nonpolar-to-Polar Phase Transition of a Chiral Ionic Plastic Crystal and Switch of the Rotation Symmetry

The synthesis of a new ionic plastic crystal, tetra­ethyl­ammonium-<i>d</i>₂₀ d-10-camphor­sulfonate, is reported. The crystal has three solid phases, the structures of which were determined by single-crystal X-ray diffraction (XRD). XRD analysis revealed a phase transition from nonpolar space group <i>P</i>2₁2₁2 to polar space group <i>P</i>2₁ with increasing temperature. The dynamics of the d-10-camphor­sulfonate anion and the tetra­ethyl­ammonium-<i>d</i>₂₀ cation was investigated by variable-temperature ¹H and ²H solid-state NMR spectroscopy. The anion showed swing motion in high-temperature phases, which is in good agreement with the disorder observed in XRD analysis. The cation showed uniaxial rotation even in the low-temperature phase. The rotation axis of the tetrahedral structure showed a transition from the two-fold axis to the three-fold axis with the phase transition

The Role of a Three Dimensionally Ordered Defect Sublattice on the Acidity of a Sulfonated Metal–Organic Framework

Understanding the role that crystal imperfections or defects play on the physical properties of a solid material is important for any application. In this report, the highly unique crystal structure of the metal–organic framework (MOF) zirconium 2-sulfoterephthalate is presented. This MOF contains a large number of partially occupied ligand and metal cluster sites which directly affect the physical properties of the material. The partially occupied ligand positions give rise to a continuum of pore sizes within this highly porous MOF, supported by N₂ gas sorption and micropore analysis. Furthermore, this MOF is lined with sulfonic acid groups, implying a high proton concentration in the pore, but defective zirconium clusters are found to be effective proton trapping sites, which was investigated by a combination of AC impedance analysis to measure the proton conductivity and DFT calculations to determine the solvation energies of the protons in the pore. Based on the calculations, methods to control the p<i>K</i>_a of the clusters and improve the conductivity by saturating the zirconium clusters with strong acids were utilized, and a 5-fold increase in proton conductivity was achieved using these methods. High proton conductivity of 5.62 × 10^–3 S cm^–1 at 95% relative humidity and 65 °C could be achieved, with little change down to 40% relative humidity at room temperature