Front Pharmacol
September 2024
Here we report a partially oxidized palladium nanodot (Pd/PdO ) catalyst with a diameter of around 4.5 nm. In aqueous CO -saturated 0.
View Article and Find Full Text PDFThe efficient electrocatalysts for many heterogeneous catalytic processes in energy conversion and storage systems must possess necessary surface active sites. Here we identify, from X-ray photoelectron spectroscopy and density functional theory calculations, that controlling charge density redistribution via the atomic-scale incorporation of heteroatoms is paramount to import surface active sites. We engineer the deterministic nitrogen atoms inserting the bulk material to preferentially expose active sites to turn the inactive material into a sufficient electrocatalyst.
View Article and Find Full Text PDFPlatinum (Pt) nanocrystals have demonstrated to be an effective catalyst in many heterogeneous catalytic processes. However, pioneer facets with highest activity have been reported differently for various reaction systems. Although Pt has been the most important counter electrode material for dye-sensitized solar cells (DSCs), suitable atomic arrangement on the exposed crystal facet of Pt for triiodide reduction is still inexplicable.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
October 2007
Copper phthalocyanine-doped TiO2 microcavities were fabricated by chemistry method. Their spectrum characterization was studied by Fourier transform infrared (FTIR) and Raman spectroscopy, and their fine structure was analyzed by X-ray absorption fine structure (XAFS). The results show that there is interaction of copper phthalocyanine (CuPc) and TiO2 microcavities after TiO2 microcavities was doped with CuPc.
View Article and Find Full Text PDFFor Candida rugosa lipase (CRL) catalyzed hydrolysis of racemic 1-phenethyl acetate, both the weakly acidic pH (pH 6.0) and the addition of 1 mM copper (II) ion enhanced the enzyme activity and enantioselectivity (E value) about twofold, as compared with that under neutral pH and noadditive conditions. The decrease of activation free energy (DeltaG) and increase of k(cat)(R)/k(cat)(S) at weakly acidic pH and/or in the presence of copper (II) characterized the kinetic behavior of CRL.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
December 2005
To study the spectral characteristic of TiO2/SnO2, TiO2/SnO2 composite oxide with SnO2 inside kernel was fabricated by colloid chemistry method, and was studied with UV-visible absorption spectrum, X-ray diffraction and infrared spectrum. The results showed that the bandgap widths of TiO2 and TiO2/SnO2 were 4.13 and 3.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
February 2003
The alpha-Fe2O3 ultrafine particles were equally dispersed in the solutions of stearic acid/n-hexane/chloroform by the ultrasonic method, the surfaces of the alpha-Fe2O3 ultrafine particles were decorated by stearic acid, and the alpha-Fe2O3 ultrafine particles decorated had very good flowage characteristic. Before alpha-Fe2O3 ultrafine particles were decorated, the UV absorption was very strong at wavelengths shorter than 290 nm, and there was a shoulder peak at 330 nm. The absorption band edges of alpha-Fe2O3 ultrafine particles was at 392 nm, and shifted toward blue, which was in contrast with that of bulk Fe2O3.
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