Teppei Yamada 교수

Proton conductive materials become important for their utility to electrolytes of fuel cells or sensors. The proton conductivity of a one-dimensional coordination polymer, ferrous oxalate dihydrate, was evaluated and found to show 1.3 mS cm(-1) at ambient temperature. The proton conductivity of this compound is extremely high at ambient temperature without any strong acidic group, and this result is suggestive of new proton conductive materials consisting of coordination polymers.

A noncoordinating hydroxyl group was introduced into a metal-organic framework (MOF) by a procedure involving a protection, complexation, and deprotection (PCD) reaction sequence, and the crystal structure of a novel MOF, [Zn(dhybdc)(bpy)] x 4 DMF (1), was determined. 1 did not have an interpenetrated structure. The three-dimensional pores had large apertures. Results showed that the PCD method is a novel synthetic method for the introduction of various functional groups into MOFs.

Abstract Proton-conductive electrolytes are key materials in fuel cells. We introduced acidic functional groups into a porous coordination polymer (PCP), or metal–organic framework (MOF), and constructed proton-conductive PCP/MOFs. To achieve this, a novel synthetic method for introducing acidic groups in PCP/MOF was invented. The proton conductivities of various PCP/MOF materials were investigated by AC impedance spectroscopy, and some of the materials showed high proton conductivity up to 8 ×

MIL-101(Fe) was investigated as a cathode material of lithium ion batteries. A battery test reveals that MIL-101(Fe) shows a charge and discharge capacitance of 110 mA h g^-1. It also showed reversible charge and discharge cycles and uptake of 0.62 Li/Fe after 100 cycles, which is the highest loading amount ever reported for the carboxylic MOFs. It also operates in the temperature range up to 350 °C and showed a good high thermal stability.

Abstract One-dimensional (1D) coordination polymers, M(dhbq)·nH2O (M = Mg, Mn, Co, Ni, and Zn, H2(dhbq) = 2,5-dihydroxy-1,4-benzoquinone, n = 2, 2.5, or 3), were synthesized and their structures were investigated using the Rietveld refinement method. They have 1D structure and were isostructural. From water uptake measurements, thermogravimetry, and elemental analysis, new 2.5 hydrate states were discovered. The proton conductivity of M(dhbq) was found to depend on the metal species and the quan

A large Seebeck coefficient (<i>S</i> _e) of 1.9 mV K^-1 was recorded for the I^-/I₃ ^- thermocell by utilizing the host-guest complexation of hexakis(2,3,6-tri-<i>O</i>-methyl)-α-cyclodextrin (Me₁₈-α-CD) with the oxidized iodide species. The thermocell measurement and UV-vis spectroscopy unveiled the formation of an Me₁₈-α-CD-pentaiodide (I₅ ^-) complex, which is in remarkable contrast to the triiodide

The high Seebeck coefficient of an I–/I3– thermocell was achieved by introducing host molecule PEGylated α-cyclodextrin (TEG-α-CD), which showed thermally induced phase transition. The host captures I3– at the cold side of the thermocell, which increased Se up to +2.4 mV/K. Notably, the maximum Se value of +4.2 mV/K was observed in the temperature range between 31 and 37 °C, which was achieved as a consequence of the phase transition between a hydrophilic phase to a hydrophobic phase. At the low

We present the solvothermal syntheses, X-ray crystal structures, and gas sorption properties of a series of zinc−dicarboxylate−polypyridine where the dicarboxylate is 1,4-benzenedicarboxylate, 4,4′-biphenyldicarboxylate, or sulfone-4,4′-biphenyldicarboxylate and the polypyridine is bipyridine or 1,4-bis(4-pyridylethynyl)benzene. The structures consist of hierarchical two-, three-, and four-blade dimer or trimer nodes which generate the square or triangular topologies of the metal-carboxylate lay