We describe the synthesis of novel monocrystalline FeCo nanowires encapsulated inside multiwalled carbon nanotubes (MWNTs). These FeCo nanowires exhibit homogeneous Fe and Co concentrations and do not contain an external oxide layer due to the presence of insulating nanotube layers. The method involves the aerosol thermolysis of toluene-ferrocene-cobaltocene solutions in inert atmospheres. The materials have been carefully characterized using state-of-the-art high-resolution transmission electron microscopy (HRTEM), electron-energy-loss spectroscopy (EELS), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), electron diffraction, HREELS-STM elemental mapping, X-ray powder diffraction, and SQUID magnetometry. We noted that the formation of FeCo alloys occurs at relatively low pyrolytic temperatures (e.g., 650-750 degrees C). These single-crystal nanowires, which have not been reported hitherto, always exhibit the FeCo (110) plane parallel to the carbon nanotube axis. The FeCo nanomaterials have shown large coercive fields at room temperature (e.g., 900 Oe). We envisage that these aligned ferromagnetic nanowires could be used in the fabrication of high-density magnetic storage devices and magnetic composites.

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The assembly of two‐dimensional (2D) transition‐metal oxides and reduced graphene oxide (RGO) has shown great potential in photocatalysis, energy storage, and photoelectric devices. In the work, we present a 3‐aminopropyltriethoxysilane (APTES)‐induced interfacial assembly route for preparation of a new type of 2D TiO2@RGO hybrid nanostructure. Benefiting from the electrostatic interaction between APTES and RGO, followed by the hydrolysis of APTES, an ultrathin SiO2 layer is first well grown into the surface of RGO. Subsequently, ultrathin TiO2 nanosheets (about 4 nm in thickness) are uniformly decorated onto the surface of silica‐modified RGO. These robust TiO2 nanosheets interconnect each other and form a unique net‐like architecture. Significantly, the TiO2@RGO products show superior structural stability. Consequently, the TiO2@RGO product annealed at 750 °C demonstrates an excellent photocatalytic activity and a good cycling life for degradation of organic dyes such as methyl orange (MO), rhodamine B (RhB) and methyl blue (MB) owing to the unique construction and enhanced synergistic effect.

Ultrasmall TiO2 nanoparticles@graphene composites with superior photocatalytic activity have been designed by a facile glucosamine-assisted hydrothermal strategy.