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Abstract: By using different dual-template combinations, four types of mesoporous silica materials with different morphologies were successfully synthesized. A solid-sphere mesoporous (SSM) silica was obtained using a combination of tri-block copolymer (F127) and 1,12-diaminododecane (DADD), but when F127 was substituted with poly(vinylpyrrolidone) (PVP), a leaf-shaped mesoporous (LSM) silica was obtained. In addition, a hollow-sphere mesoporous (HSM) silica was obtained by using a combination of PVP and dodecylamine (DDA), but a cotton-like mesoporous (CLM) silica was obtained using F127 instead of PVP. All four types of synthesized materials were characterized by SEM, TEM, XRD, and N2 adsorption–desorption isotherms, and the results showed that all of them exhibited high surface area, large pore volume, worm-like pore structure, and beautiful shapes. The results of storage experiments revealed that the HSM and CLM showed good adsorption and storage properties. The HSM (the largest pore volume) seemed to have the larger storage capacity when compared to the CLM, albeit CLM had the highest surface area among all. [Copyright &y& Elsevier]

Abstract: A hollow sphere neodymium embedded mesoporous silica material (NEMS) has been synthesized successfully by using neutral 1,12-diaminododecane as template and embedding Nd into the framework simultaneously. It is interesting that a lamellar structured material with MSU-V structure was obtained if only DADD was used as template without embedding of Nd. The synthesized materials were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), BET method, thermal gravimetry/differential thermal analysis (TG/DTA), and X-ray photoelectron spectroscopy (XPS). The hollow sphere morphology was observed by TEM images and clearly revealed the structure of NEMS molecular sieves. Both XRD and XPS results confirmed that the Nd atoms were incorporated into the framework of mesoporous materials. The TG/DTA results verified the good thermal stability of the synthesized NEMS material. The surface area of samples with Si/Nd molar ratio from 10 to 60 reached from 543 to 1103m2 g−1, respectively. It also found that the Nd embedded mesoporous silica material showed good catalytic activity and selectivity towards the oxidation of styrene, proportional to the neodymium content in the catalysts. [Copyright &y& Elsevier]

Abstract: A novel self-humidifying membrane electrode assembly (MEA) has been successfully prepared by adding both a hydrophilic organic polymer (polyvinyl alcohol, PVA) and an inorganic oxide (silica) to the anode catalyst layer. This MEA shows excellent self-humidification performance under low-humidity conditions. A sample containing 3 wt.% PVA and 3 wt.% silica in the anode catalyst layer achieves a current density as high as 1100 mA cm−2 at 0.6 V, and the highest peak power density is 780 mW cm−2, operating at 60 °C and 15% relative humidity for both anode and cathode. The sample also shows excellent stability at low-humidity: after 30 h of continuous operation under the same conditions, the current density decreases just slightly, from 1100 mA cm−2 to ca. 900 mA cm−2, whereas with MEAs to which only PVA or silica alone had been added, the current densities after 30 h is just 700 mA cm−2 and 800 mA cm−2, respectively. The improved self-humidification performance can be attributed to the synergistic effect of two hygroscopic materials in the anode catalyst layer. [Copyright &y& Elsevier]

Highlights: [•] Mesoporous silica supported Pd-promoted gold catalyst was prepared. [•] Low Pd/Au atomic ratio of 0.05/1 can effectively decrease the gold particles size. [•] Pd0.2Au shows 8 and 3 times higher activity than the Au/MSN and Pd/MSN respectively. [•] Catalysts were characterized by XRD, N2 sorption, DRUV-vis, TPR, XPS and TEM. [Copyright &y& Elsevier]

Abstract: A high-performance, gold-promoted Pd catalyst with mesoporous hollow silica spheres as support, PdAu/MHSS, was prepared using an impregnation–reduction approach. The catalyst showed 10 times higher activity than commercial Pd/C catalyst and 6 times higher activity than Pd/MHSS catalyst. The conversion of phenol was 100% within 30min of reaction at 80°C. The catalyst was characterized by XRD, XPS, and TEM, which revealed that its high performance may result from both the high dispersion of active components on the MHSS, caused by the addition of gold, and the interaction between palladium and gold. [Copyright &y& Elsevier]

Abstract: In this work, a membrane electrode assembly (MEA) for proton exchange membrane fuel cell (PEMFC) operating under no external humidification has been successfully fabricated by using a composite Pt/SiO2/C catalyst at the anode. In the composite catalyst, amorphous silica, which originated from the hydrolysis of tetraethyl orthosilicate (TEOS), was immobilized on the surface of carbon powder to enhance the stability of silica and provide a well-humidified surrounding for proton transport in the catalyst layer. The characteristics of silica in the composite catalyst were investigated by XRD, SEM and XPS analysis. The single cell tests showed that the performance of the novel MEA was comparable to MEAs prepared using a standard commercial Pt/C catalyst with 100% external humidification, when both were operated on hydrogen and air. However, in the absence of humidification, the MEA using Pt/SiO2/C catalyst at the anode continued to show excellent performance, while the performance of the MEA containing only the Pt/C catalyst rapidly decayed. Long-term testing for 80 h further confirmed the high performance of the non-humidified MEA prepared with the composite catalyst. Based on the experimental data, a possible self-humidifying mechanism was proposed. [ABSTRACT FROM AUTHOR]

Abstract: By using two non-ionic surfactants, 1,12-diaminododecane and a triblock copolymer surfactant F127, as templates, grape-like solid spheres of super-microporous silica (SMS) with ordered, worm-like pore structures have been successfully synthesized, then characterized by SEM/TEM, XRD, TG/DTA, etc. In a sample synthesized at 70°C, well-formed grape-like spheres with worm-like pores were observed by SEM and TEM. The average pore size is ca. 1.87nm and the specific surface area of the spheres is 865m2/g. The hydrogen storage capacity of the sample Pd/SMS-70-C, prepared by supporting 5wt% palladium on SMS (synthesized at 70°C), is up to 2.56wt% at 1.2MPa hydrogen pressure. [Copyright &y& Elsevier]