Yuki Kawashima

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Two phthalocyanines possessing carboxylate groups ((TBA)4H2Pc·1 and (TBA)4H2Pc·2) form 1:2 supramolecular complexes with lithium cation-encapsulated C60 (Li(+)@C60) [H2Pc·1(4-)/(Li(+)@C60)2 and H2Pc·2(4-)/(Li(+)@C60)2] in a polar mixed solvent. From the UV-vis spectral changes, the binding constants (K) were estimated as ca. 10(12) M(-2). Upon the(More)
A supramolecular binding occurred between lithium ion encapsulated [60]fullerene (Li(+)@C(60)) and sulfonated tetraphenylporphyrins ([MTPPS](4-) M = H(2) and Zn) in a benzonitrile solution. Photoexcitation of Li(+)@C(60)/[MTPPS](4-) results in formation of a long-lived charge-separated state by photoinduced electron transfer.
Rate constants of photoinduced electron transfer between spherical fullerenes were determined using triscandium nitride encapsulated C80 fullerene (Sc3N@C80) as an electron donor and the triplet excited state of lithium ion-encapsulated C60 fullerene (Li(+)@C60) as an electron acceptor in polar and less polar solvents by laser flash photolysis measurements.(More)
An ionic endohedral metallofullerene (Li(+)@C60) with mild hydrophilic nature was combined with graphene oxide (GO) to construct a donor-acceptor composite in neat water. The resulting composite was characterised by UV-Vis and Raman spectroscopy, powder X-ray diffraction, dynamic light scattering measurements and transmission electron microscopy.(More)
Goniodomin A is a marine polyether macrolide natural product isolated from the dinoflagellate Alexandrium hiranoi. In this paper, we report stereocontrolled, convergent synthesis of a fully functionalized C12-C36 fragment of goniodomin A. The synthesis of the C12-C25 vinylstannane involved a Wittig reaction and a reductive cycloetherification for the(More)
Lithium-ion-encapsulated fullerene (Li(+) @C60 ) exhibits greatly enhanced reactivity in photoinduced electron-transfer reduction with electron donors compared with pristine C60 . The enhanced reactivity of Li(+) @C60 results from the more positive one-electron reduction potential of Li(+) @C60 (+0.14 V versus a standard calomel electrode (SCE)) than that(More)
A photoelectrochemical solar cell composed of supramolecular nanoclusters of lithium encapsulated fullerene and zinc sulphonated meso-tetraphenylporphyrin exhibits significant enhancement in the photoelectrochemical performance as compared with the reference system containing only a single component.
We have deposited cluster-free P-doped a-Si:H films using SiH<inf>4</inf>+PH<inf>3</inf> multi-hollow discharge plasma CVD method. We have measured dependence of a deposition rate and SiH emission intensity on a gas flow rate ratio R=[PH<inf>3</inf>]/[SiH<inf>4</inf>]. The increase of deposition rate with R is much larger than that of SiH emission(More)
Photoinduced electron-transfer processes in a carbonaceous supramolecular combination of a tubular host and a C60 guest were investigated with time-resolved transient absorption spectra upon laser flash photolysis. Following the formation of triplet charge-separated species via electron transfer from the host to the guest, a rapid back electron transfer(More)
We have fabricated Si quantum dot-sensitized solar cells by three assembling methods; the conventional method and two novel methods in which Si nanoparticles/TiO<inf>2</inf> blend paste is coated onto FTO glass, or TiO<inf>2</inf> film. The highest current density is realized s solar cell for which Si nanoparticles/TiO<inf>2</inf> blend paste is coated onto(More)