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A lot of progress has been made in rechargeable lithium-ion battery (LIB) technology research in the last decade, even so, renewed developmental efforts must be pursued to better improve energy density, capacity retention and rate capability. This review discusses the role that one-dimensional (1D) nanomaterials can play towards development of next-generation LIBs. Electrode nanoengineering, interfacial kinetics and high-volume manufacturing are critical issues limiting energy density, electrochemical performance and material viability. These points are discussed, as are the advantages of deploying these nanomaterials in rechargeable LIB devices. Current data from literature is indicative of laboratory-scale success as these 1D nanomaterials display excellent capacity retention, high-rate capability and long cycle life emanating from high mechanical strength, resilience and short charge carrier diffusion distance. However, significant advances are required to translate these achievements into commercial scale deployment. [ABSTRACT FROM AUTHOR]

The Raman spectrum of gallium oxide (β-Ga2O3 nanowires with [401] growth direction is identical to that of the bulk Ga2O3 [Y. C. Choi et al. Adv. Mater. 12, 746 (200] while that of β-Ga2O3 nanowires with [401] growth direction is redshifted by 4–23 cm-1 [Y. H. Gao et al. Appl. Phys. Lett. 81, 2267 (2002)]. Here we report the Raman and Fourier transform infrared spectra of β-Ga2O3 nanowires with [110] growth direction which is blueshifted relative to the bulk spectra by ∼10–40 cm-1. Based on a first principles calculation of the strain dependence of Raman mode frequencies in bulk β-Ga2O–, we correlate the observed frequency shifts to growth-direction-induced internal strains in the nanowires. [ABSTRACT FROM AUTHOR]

We report the first ever demonstration of using silane directly in the gas phase and molten gallium in a microwave plasma for bulk nucleation and growth of single-crystal quality silicon nanowires. Multiple nanowires nucleated and grew from micron- to millimetre-sized gallium droplets. The resulting nanowires were tens to hundreds of nanometres in diameter and were tens to hundreds of microns long. Transmission electron microscopy results confirmed the nanowires to be single crystalline, devoid of structural defects, and grown along the [inline image] direction. The as-synthesized silicon nanowires were sheathed with an ultrathin (<1 nm) non-uniform native oxide amorphous layer that could be directly used in the assembly of electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

In transmission electron micrography of few-layer thick graphene samples, two distinct regions, a region of superlattice and an adjacent region of parallel straight bands, are seen. These two features are explained as Moire patterns produced by (1) rotation of top part of one of the graphene layers and (2) a small change in the shape of the bottom part of the same layer. It is interesting to note that for the first time, Moire pattern of parallel straight bands is observed and satisfactorily explained. [ABSTRACT FROM AUTHOR]

The possibility to control the morphology and nucleation density of quasi-one-dimensional, single-crystalline α-Fe2O3 nanostructures by varying the electric potential of iron surfaces exposed to reactive oxygen plasmas is demonstrated experimentally. A systematic increase in the oxygen ion flux through rf biasing of otherwise floating substrates and then an additional increase of the ion/neutral density resulted in remarkable structural transformations of straight nanoneedles into nanowires with controlled tapering/aspect ratio and also in larger nucleation densities. Multiscale numerical simulations relate the microscopic ion flux topographies to the nanostructure nucleation and morphological evolution. This approach is applicable to other metal-oxide nanostructures. [ABSTRACT FROM AUTHOR]

We report near-infrared lasing in the telecommunications band in gallium antimonide semiconductor subwavelength wires. Our results open the possibility of the use of semiconductor subwavelength-wire lasers in future photonic integrated circuits for telecommunications applications. [ABSTRACT FROM AUTHOR]

The bulk nucleation and basal growth of semiconducting nanowires from molten Ga pools has been demonstrated earlier using oxygen/hydrogen plasma over molten Ga pools. Herein, we extend the above concept for bulk synthesis of oxide and sulfide nanowires of low-melting metal melts such as Sn and In. Specifically, nanowires of β-Ga2O3, β-In2O3, SnO2, α-Ga2S3, and β-In2S3 were synthesized using direct reactions between respective molten metal pools and the gases such as oxygen/hydrogen mixture for oxides and H2S for sulfides. In the case of β-Ga2O3 and SnO2, a change in the morphology from nanowires to nanobelts was observed with an increase in the synthesis temperature. No such behavior was observed in the case of β-In2O3. Furthermore, we present evidence for α-Ga2S3 nanowires, which to our knowledge is being reported for the first time in the literature. Our studies with the sulfide nanowires suggest that H2S reacts directly at the moltenmetal surface to form gallium sulfide. Finally, we discuss the role of chamber pressure and hydrogen on the size distribution of nanostructured β-Ga2O3 and SnO2. [ABSTRACT FROM AUTHOR]

Silicon nanowires will find applications in nanoscale electronics and optoelectronics both as active and passive components. Here, we demonstrate a low-temperature vapor–liquid–solid synthesis method that uses liquid-metal solvents with low solubility for silicon and other elemental semiconductor materials. This method eliminates the usual requirement of quantum-sized droplets in order to obtain quantum-scale one-dimensional structures. Specifically, we synthesized silicon nanowires with uniform diameters distributed around 6 nm using gallium as the molten solvent, at temperatures less than 400 °C in hydrogen plasma. The potential exists for bulk synthesis of silicon nanowires at temperatures significantly lower than 400 °C. Gallium forms a eutectic with silicon near room temperature and offers a wide temperature range for bulk synthesis of nanowires. These properties are important for creating monodispersed one-dimensional structures capable of yielding sharp hetero- or homointerfaces. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]