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The rational design of catalytic materials from the reaction characteristics is expected to be a useful strategy to create highly efficient catalysts. Herein, according to a well-established reaction pathway of epoxide hydration catalyzed a dual-molecular system of Co3+/salen in which a high concentration of active sites is favorable to enhance the activity, we provide an alternative way to prepare a highly efficient heterogeneous catalyst with a high concentration of Co3+/salen from the polymerization of vinyl-functionalized salen monomers followed by the loading of Co3+ species (Co3+/POL-salen). Co3+/POL-salen has a hierarchical porosity and an extraordinary hydrothermal stability. Importantly, catalytic tests in epoxide hydration demonstrate that Co3+/POL-salen affords excellent high activities, which are even better than those of the homogeneous version. This phenomenon is related to the very high concentration of Co3+/salen in the catalyst. In addition, this catalyst can be recycled readily because of its excellent hydrothermal stability. [ABSTRACT FROM AUTHOR]

High quality self-assembled ZnS mesoporous nanospheres have been successfully synthesized by a facile solvothermal method. The sample was synthesized using ethylene glycol aqueous solution without any surfactant assistance. Size and shape control of the ZnS mesoporous nanospheres is achieved by simple adjustments of the reactants' concentration. Investigation results show that ZnS spheres are made up of small ZnS nanocrystallites and show good photocatalytic activity in the degradation of MB under the irradiation of ultraviolet light because of their mesoporous structures. [ABSTRACT FROM AUTHOR]

Abstract: Humidity sensors based on K-doped mesoporous silica SBA-15 were prepared and characterized by XRD, SEM, TEM and N2 adsorption-desorption isotherms. The humidity sensing test results show that KCl doping improves the sensing characteristic of humidity sensors. The optimal result is obtained via sample 50wt% KCl-doped SBA-15, which exhibits an excellent linearity in the whole humidity range of 11%-95%. It also shows satisfactory reversibility and fast responses to the environmental moisture. The investigation of the humidity sensitive characteristics of the K-doped SBA-15 sensor shows that this material could have good prospects of application in humidity sensor. [Copyright &y& Elsevier]

Abstract: Pt-doped mesoporous indium oxide (In2O3) has been successfully obtained by a simple and effective in situ nanocasting method. The resultant samples were characterized by XRD, FE-SEM, TEM, N2 physisorption, XPS and EDX. The gas sensing properties for hydrogen sulfide (H2S) of the Pt-doped mesoporous In2O3 specimens were also examined. The results exhibit those In2O3 specimens possess much higher response to H2S even at low concentration of 2ppm and a lower optimum working temperature of 150°C. A possible mechanism was also provided to explain the improvement of the sensing properties. [Copyright &y& Elsevier]

Abstract: Dye Coumarin 151 was postgrafted into the rodlike SBA-15 mesoporous materials, which were synthesized by a direct hydrothermal synthesis method and further modified by an organic silane with a terminal amino group. Characterization by powder X-ray diffraction, N2 adsorption–desorption, transmission electron microscopy, photoluminescence and scanning electron microscopy were carried out. Small-angle X-ray diffraction and N2 adsorption–desorption characterizations showed that these dye containing materials remained as ordered mesostructures and the pore size was from 6nm for blank sample to 3.6nm for postgrafting sample. PL characterization of composite samples exhibited optical properties with different dye concentrations. The characterization showed the existence of Coumarin 151 in the channels of SBA-15 and the composite materials with novel optical properties enabled possible applications in optical sensing and electron acceptors. [Copyright &y& Elsevier]