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Fe2O3 nanosheets and nanoparticles are grown on graphene by simply varying reaction solvents in a facile solvothermal/hydrothermal preparation. Fe2O3 nanosheets are uniformly dispersed among graphene nanosheets, forming a unique sheet-on-sheet nanostructure. Due to the structure affinity between two types of two dimensional nanostructures, graphene nanosheets are separated better by Fe2O3 nanosheets compared to nanoparticles and their agglomeration is largely prevented. Alarge surface area of 173.9 m2 g-1 is observed for Fe2O3-graphene sheet-on-sheet composite, which is more than two times as large as that of Fe2O3-graphene particle-on-sheet composite (81.5 m2 g-1). The sheet-on-sheet composite is found to be better suitable as an anode for Li-ion battery. A high reversible capacity of 662.4 mAh g-1 can be observed after 100 cycles at 1000 mA g-1. The substantially improved cycling performance is ascribed to the unique structure affinity between Fe2O3 nanosheets and graphene nanosheets, thus offering complementary property improvement. [ABSTRACT FROM AUTHOR]

Metal and metal oxide nanoparticles supported on high surface area materials are widely used in industry for fuel and chemical production and for environmental pollution control, but preventing nanosized particle sintering has remained a great challenge. In this paper, we report that Ni−Cu alloy nanoparticles can be effectively stabilized in cubic mesostructured silica (SBA-16) following a conventional impregnation and thermal treatment process. The three-dimensional interconnected cage structure of the mesoporous SBA-16 allows good accessibility of reactant gas molecules to the metal nanoparticles and confines these particles within its nanosized cages. This confinement hinders metal nanoparticle migration and sintering under harsh conditions. A new class of regenerable metal-based adsorbents which can remove sulfur impurities from warm syngas stream down to less than 60 parts per billion by volume (ppbv) is described. This same confinement strategy is expected to have impact for minimizing sintering or particle coarsening of nanosized materials employed in other applications. [ABSTRACT FROM AUTHOR]