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The article analyzes the post-synthesis of Ti-SBA-15 materials in supercritical CO2-ethanol solution. It cites that silicates are substituted by Ti, a type of efficient catalyst for epoxides production. The study uses several techniques, such as x-ray photoelectron spectroscopy and x-ray diffraction, in characterizing the resultant of Ti-SBA-15 materials. The results showed that slight presence of H2O in the reaction medium may result to some TiO2 nanoparticles.

Palladium-sepiolite catalysts were prepared by immobilizing Pd2 sepiolite using an ionic liquid containing a guanidine cation, followed by reduction with hydrogen at 150 °C. The resulting composites were characterized by different techniques. X-Ray photoelectron spectroscopy analysis showed that the loaded Pd existed mainly in the form of Pd0, with a small amount of its oxides, and distributed uniformly on sepiolite with particle size about 5 nm, as confirmed by transmission electron microscopy examination. X-Ray diffraction analysis indicated that the sepiolite retained its original structure after deposition of Pd nanoparticles. The activities of the Pd-sepiolite catalysts for hydrogenations of some alkenes (e.g., cyclohexene and 1,3-cyclohexdiene) and Heck reactions were investigated. It was demonstrated that the as-prepared catalysts exhibited very high efficiency for these reactions. [ABSTRACT FROM AUTHOR]

A novel support of the Ru nanoparticles was achieved by combination of electrostatic force and coordination. The Ru catalyst was used as heterogeneous catalyst for hydrogenation of arene. This catalyst is very active for the hydrogenation of benzene to cyclohexane even under mild conditions. The TOF of this Ru catalyst is 85.3 mol mol−1 h−1 at 20 °C and 1.0 MPa for complete hydrogenation of benzene. The catalytic activity did not decrease after other five runs. The excellent performance of this catalyst demonstrated that there existed synergistic effects among 1,1,3,3-tetramethylguanidinium, mesoporous SBA-15, and Ru nanoparticles. [ABSTRACT FROM AUTHOR]

A low-temperature, efficient and one-step deposition method, in which Mn(CH3COO)2·4H2O serves as precursor and O2 as oxidant, was employed to deposit Mn3O4 nanoparticles on multi-walled carbon nanotubes (MWCNTs) in ethanol solution at 150 and 200 °C. The resulting Mn3O4/MWCNT composites were characterized by means of different techniques including x-ray diffraction, x-ray photoelectron spectroscopy and transmission electron microscopy. It was indicated that the Mn3O4 nanoparticles were attached uniformly on MWCNTs with sizes less than 10 nm, and the loading amount of Mn3O4 could be tuned by changing the initial weight ratio of Mn(CH3COO)2·4H2O/MWCNT. The electrochemical behavior of the Mn3O4/MWCNT composites was examined by cyclic voltammetry, and the result indicated the specific capacitance of the composite electrode was 330 F g[?]1, nearly 18 times higher than that of the pure MWCNT electrode. The good performance of the as-prepared composites as electrode material may be attributed to the synergistic effects of the Mn3O4 nanoparticles and the MWCNTs. [ABSTRACT FROM AUTHOR]

The article investigates the facile synthesis of high quality TiO2 nanocrystals in ionic liquid. The researchers have demonstrated a facile way to synthesize size-controlled anstase nanocrystals. These nanocrystals may be useful for basic studies on size- and shape-dependent properties of TiO. The researchers believed that the method will open a new way to fabricate nanostructure materials, and systematic study is in progress.

A universal strategy was developed for the preparation of high-temperature-stable carbon nanotube (CNT) -supported metal nanocatalysts by encapsulation with a mesoporous silica coating. Specifically, we first showed the design of one novel catalyst, Pt@CNT/SiO2, with a controllable mesoporous silica coating in the range 11−39 nm containing pores ≈3 nm in diameter. The hollow porous silica shell offers a physical barrier to separate Pt nanoparticles from contact with each other, and at the same time the access of reactant species to Pt was not much affected. As a result, the catalyst showed high thermal stability against metal particle agglomeration or sintering even after being subjected to harsh treatments up to 500 °C. In addition, degradation in catalytic activity was minimized for the hydrogenation of nitrobenzene over the catalyst treated at 300 °C for 2 h. The scheme was also extended to coat porous silica onto the surfaces of CuRu@CNT and the resultant catalyst thereby can be reusable at least four times without loss of activity for the hydrogenolysis of glycerol. These results suggest that the as-prepared nanostructured CNT-supported catalysts may find promising applications, especially in those processes requiring rigorous conditions. [ABSTRACT FROM AUTHOR]