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Pt-based one-dimensional hollow nanostructures are promising catalysts in fuel cells with excellent activity. Herein, one-dimensional hollow FePt nanochains were shown to be efficient nanocatalysts in the hydrolysis of NaBH4. The characterization of composition, structure and morphology identifies an ultrathin shell (∼3 nm) with uniformly distributed Fe30Pt70 constituents. The H2 generation rate of hollow Fe30Pt70 nanochains achieves 16.9 l/(min · g) at room temperature, while the activation energy is as low as 17.6 kJ mol-1 based on the fitting over the whole reaction time span. After the catalysis of NaBH4 hydrolysis, the morphology and composition of hollow FePt nanochains remain unchanged. Furthermore, the structural stability of hollow FePt nanochains under Ga+ ion irradiation is clarified. Theoretical simulation indicates that the stopping range of such a Fe30Pt70 shell is 7.7 keV, which offers a prediction that structure evolves diversely under Ga+ ions below and above such energy. The Ga+ ion irradiation experiments show a consistent trend with the simulation, where Ga+ ions with kinetic energy of 30 keV make the hollow architecture subside and sputter away, while Ga+ ions with kinetic energy of 5 keV only etch the top and lead to an eggshell structure.

Catalysis by supported single metal atoms has demonstrated tremendous potential for practical applications due to their unique catalytic properties. Unless they are strongly anchored to the support surfaces, supported single atoms, however, are thermodynamically unstable, which poses a major obstacle for broad applications of single-atom catalysts (SACs). In order to develop strategies to improve the stability of SACs, we need to understand the intrinsic nature of the sintering processes of supported single metal atoms, especially under various gas environments that are relevant to important catalytic reactions. We report on the synthesis of high number density Pt1/Fe2O3 SACs using a facial strong adsorption method and the study of the mobility of these supported Pt single atoms at 250 °C under various gas environments that are relevant to CO oxidation, water-gas shift, and hydrogenation reactions. Under the oxidative gas environment, Fe2O3 supported Pt single atoms are stable even at high temperatures. The presence of either CO or H2 molecules in the gas environment, however, facilitates the movement of the Pt atoms. The strong interaction between CO and Pt weakens the binding between the Pt atoms and the support, facilitating the movement of the Pt single atoms. The dissociation of H2 molecules on the Pt atoms and their subsequent interaction with the oxygen species of the support surfaces dislodge the surface oxygen anchored Pt atoms, resulting in the formation of Pt clusters. The addition of H2O molecules to the CO or H2 significantly accelerates the sintering of the Fe2O3 supported Pt single atoms. An anchoring-site determined sintering mechanism is further proposed, which is related to the metal-support interaction.

Graphene oxide (GO) sheets were synthesized via a modified Hummers method. GO dispersion with a high concentration of 6 mg ml−1 was chosen to form GO hydrogel, followed by chemical reduction to derive a free–standing reduced GO (rGO) film. According to the x-ray diffraction (XRD) analysis, it has a [0 0 1] crystalline orientation in the film thickness direction. The rGO film has a densely stacked laminated structure and highly anisotropic characteristic of electrical conductivities. The light-weight rGO wire also demonstrates its excellent flexible and fire-retardant characteristics. Stress–strain measurements revealed the mechanical properties of the GO film can got further improved after chemical reduction. Electrical transport measurement indicates that rGO film exhibit semiconducting behavior with negative temperature coefficient characteristic. A temperature dependence of the conductivity from 20 to 297 K reveals that the carrier transport mechanism is thermally activated band conduction above 200 K and three-dimensional (3D) Mott's variable range hopping below 100 K. The parameters such as a density of the localized electron states and a localization length of the wave function have been determined from the plot of conductivity versus (versus) temperature.

A family of Au n @(ZnO)[Formula: see text] ([Formula: see text]-16) cluster-assembled nanoparticles are studied by density-functional theory calculations. Different sizes, up to 100 atoms, are considered for several compositions. For each n, we design and construct a converged model for Au n @(ZnO)[Formula: see text] to analyze the coupling effect of adding Au atoms into ZnO outer shell. Among the optimized geometrical structures, we find that [Formula: see text]@(ZnO)[Formula: see text] has the most stable structure. The electronic properties, optical properties and catalytic activity of the [Formula: see text]@(ZnO)[Formula: see text] core-shell have been systematically investigated, which also shows consistency with the experimental results. It is found that forming a core-shell structure enhances the visible-light photocatalytic ability and [Formula: see text]@(ZnO)[Formula: see text] core-shell structure has a high catalytic efficiency for the reaction CO oxidation.

Magnesium hydroxide sulfate hydrate nanoribbons have been synthesized by a solution-phase approach, which is based on the treatment of freshly precipitated magnesium hydroxide in an alcohol–water solution containing high concentrations of magnesium sulfate. These nanoribbons had typical lengths up to the micrometre range, widths of 60–300 nm, and thicknesses of 16–50 nm.

Uniform and aligned nickel nanochains with interlaced-nanodiscs structure were first synthesized by using a template-free magnetic-field-assisted method at room temperature. The interlaced-disc nanochains were composed of nanodiscs with diameters of ∼90 nm and thicknesses of ∼10 nm. An attachment process has been proposed to explain the observed growth of the nanodiscs. With concentration of the OH− increased, the morphology of the products transforms from star- to interlaced-nanodisc-like nanochains. Systematic magnetic measurements demonstrate that the well-aligned interlaced-nanodisc-like Ni nanochains have coercivity of about 300 Oe and effective anisotropy of about five times more than the bulk value.

Boron carbide nanowires with uniform carbon nitride coating layers were synthesized on a silicon substrate using a simple thermal process. The structure and morphology of the as-synthesized nanowires were characterized using x-ray diffraction, scanning and transmission electron microscopy and electron energy loss spectroscopy. A correlation between the surface smoothness of the nanowire sidewalls and their lateral sizes has been observed and it is a consequence of the anisotropic formation of the coating layers. A growth mechanism is also proposed for these growth phenomena.

A systematic microstructure investigation on the boron carbonitride (BCN) nanotubes, synthesized by bias-assisted hot-filament chemical vapour deposition, is reported. The BCN nanotubes were found to be well-crystallized with uniform diameters and transverse connections inside. Their lengths can be over a few tens of micrometres. Transmission electron microscopy (TEM) analyses indicate that the BCN nanotubes have near zigzag graphic-layered structures with helical angles of less than 30°. Spatial-resolved electron energy loss spectroscopy (EELS) demonstrates typical sp2 bonding configuration of the nanotubes with pronounced characteristic π* and σ* peaks of boron and carbon and characteristic K-shell ionization edges of nitrogen. EELS and energy-filtered TEM analyses reveal that the inner layer of the nanotube contains mass of carbon and some amount of boron, and the outer layer and the connections across the inner walls are rich in boron. The nitrogen is found distributing in the nanotube dispersedly and traceable amount of oxygen is measured existing in the shell of the nanotube.

Well crystallized aligned zinc oxide nanoscale tubular structures have been fabricated via vapour phase growth on large area substrates. The ZnO nanotubes have regular polyhedral shapes, hollow cores with diameters of 30–100 nm, lengths over a few tens of micrometres and wall thicknesses of 4–10 nm. In morphology, the nanotubes were either straight or twisted with several straight parts. The microstructure of the tubular material was investigated in detail by using high-resolution transmission electron microscopy (HRTEM), Z-contrast imaging and compositional line profile analysis. The chemical composition of individual tubular structures was found to be stoichiometric ZnO using selected area energy dispersive x-ray spectroscopy and electron energy loss spectroscopy. X-ray diffraction (XRD) and selected area electron diffraction results indicated that the ZnO nanotubes had wurtzite crystal structure. XRD analysis and HRTEM investigations indicated the ZnO nanotubes were grown along the [001] direction. The growth of the tubular ZnO nanostructures was found to be closely related to the hexagonal nature of the ZnO crystal and the peculiar growth conditions used.