Chemistry Letters
Online ISSN : 1348-0715
Print ISSN : 0366-7022
ISSN-L : 0366-7022
Volume 40 , Issue 8
Showing 1-40 articles out of 40 articles from the selected issue
Highlight Review
  • Nobuhito Imanaka, Toshiyuki Masui, Keisuke Yasuda
    2011 Volume 40 Issue 8 Pages 780-785
    Published: August 05, 2011
    Released: July 16, 2011
    JOURNALS FREE ACCESS
    Excellent oxidation catalysts, which can completely oxidize volatile organic compounds (VOCs) and methane at moderate temperatures, have been prepared. A new concept based on the design of solid electrolytes has been applied to the preparation of the catalysts. By the synergetic effect of precious metals and rare earth oxides, complete oxidation of VOCs and methane into CO2 and steam at moderate temperatures has been realized for the present catalysts.
    The present review describes novel oxidation catalysts developed in the group of the authors. These catalysts can completely oxidize volatile organic compounds (VOCs) and methane at moderate temperatures. A new concept based on the design of solid electrolytes has been applied to the preparation of the catalysts. Fullsize Image
  • Keiichi Hirano, Isabel Piel, Frank Glorius
    2011 Volume 40 Issue 8 Pages 786-791
    Published: August 05, 2011
    Released: June 25, 2011
    JOURNALS FREE ACCESS
    N-Heterocyclic carbene (NHC)-catalyzed transformations have found increasing interest in the last years. Recently, dual catalytic approaches using NHCs in combination with a second catalyst such as another organocatalyst or a metal-based catalyst or by the NHC itself have emerged. The careful choice of the proper combination of catalysts allows two compatible yet independent catalytic systems in one-pot to undergo tandem processes. Moreover, simultaneous action of two activators in a bond-forming event enables new reactivity, which often cannot be achieved by monocatalytic approaches.
    N-Heterocyclic carbene (NHC)-catalyzed transformations have found increasing interest in the last years. Recently, dual catalytic approaches using NHC in combination with a second catalyst such as another organocatalyst or a metal-based catalyst or by the NHC itself have emerged. The careful choice of the proper combination of the catalysts allows two compatible yet independent catalytic systems in one-pot to undergo tandem processes. Moreover, simultaneous action of two activators in a bond-forming event enables new reactivity and selectivity, which often cannot be achieved by monocatalytic approaches. Fullsize Image
Letter
Editor's Choice
Letter
Editor's Choice
  • Aimin Yu
    2011 Volume 40 Issue 8 Pages 874-876
    Published: August 05, 2011
    Released: July 27, 2011
    JOURNALS OPEN ACCESS
    Poly(pyrrole) inverse opals (PPY-IO) with three-dimentional (3D) network of macropores were prepared by electropolymerization of pyrrole in the voids of polystyrene (PS) colloidal crystals and subsequently removing the PS. The as-prepared PPY-IO were then served as templates to be filled with prehydrolyzed silica sols followed by calcination to synthesize mesoporous silica spheres with well-controlled diameters. It was demonstrated that the reactant composition of the silica sol played an important role in controlling the shell thickness of the hollow spheres. Solid mesoporous silica spheres could be obtained when a concentrated TEOS sol was used. The morphology and pore structures of PPY-IO and silica spheres were characterized by SEM. TEM and small-angle XRD confirmed the ordered mesostructure of the prepared silica spheres with an average pore size of ca. 6 nm.
Letter
Editor's Choice
  • Motonari Adachi, Kei Noda, Ryo Tanino, Jun Adachi, Katsumi Tsuchiya, Y ...
    2011 Volume 40 Issue 8 Pages 890-892
    Published: August 05, 2011
    Released: July 27, 2011
    JOURNALS OPEN ACCESS
    Electrochemical impedance spectroscopy (EIS) is an excellent method to determine simultaneously many parameters concerning electron-transport processes in dye-sensitized solar cells under the same conditions as those for the cell in operation. A number of studies analyzed the electron-transport processes based on EIS measurements under dark conditions, although the photocurrent density–voltage (IV) measurements were carried out under one-sun illumination conditions. The result of EIS measurement obtained under dark conditions, however, is quite different from that obtained under illumination. The EIS measurement should thus be carried out under the same illumination conditions as the IV measurement is performed to obtain properly analyzed results in regard to the electron-transport processes. The main factor contributing to such difference between dark and illumination conditions was elucidated to be the difference in the electron density in the steady-state cell performance between dark and illumination conditions.
feedback
Top