One-dimensional Inorganic Nanostructures Research Articles

1-nm-Wide Hydrated Dipole Arrays Regulate AuNW Assembly on Striped Monolayers in Nonpolar Solvent

Summary We show that striped phases of horizontally oriented phospholipids presenting 1-nm-wide orientable dipole arrays can order and straighten flexible 2-nm-diameter gold nanowires (AuNWs) with lengths (up to 1 μm) that greatly exceed the template pitch (∼7.5 nm). AuNW ordering can extend over areas > 100 μm2. Whereas wires bundle in solution, with contact between ligand shells, wires adsorbing to the template separate to much larger center-to-center distances (e.g., 12–30 nm) near multiples of the template pitch, consistent with repulsive interactions between wires emerging during interactions with dipole arrays in the template. AuNW assembly was carried out in cyclohexane, a nonpolar solvent. Interestingly, we found that wire ordering was contingent on the extent of phospholipid headgroup hydration and the presence of excess oleylamine, which assembled into hemicylindrical micelles around the hydrated headgroups. Together, these components generated a protected polar environment that enabled the phospholipid headgroups to function collectively to regulate AuNW assembly.

Hydrothermal synthesis of single-crystalline one dimensional β-BaB2O4 microrods with second order nonlinear optical properties

The second harmonic generation (SHG) have been the most extensively used and well understood nonlinear optics phenomenon. It implies a generation of new output frequency, twice larger than that of the incident laser radiation. Therefore, it is of key importance to propose appropriate second harmonic generation media. To date, the one-dimensional inorganic nanostructures are expected to exhibit a strong nonlinear optical response. Herein, we fabricated single-crystalline one-dimensional β-BaB2O4 microrods via a facile hydrothermal procedure and subsequent annealing using barium chloride, sodium borate and hydrochloric acid as starting materials. The fabricated β-BaB2O4 microrods generated good spectral response within the excitation range of 800–1064 nm. The SH intensity of the microrods increased linearly with excitation intensity Iω (In, n = 2.11), which demonstrated the quasi two-photon dependence. These results reveal that the fabricated β-BaB2O4 microrods are promising for future nonlinear optical applications.

ChemInform Abstract: One‐Dimensional Inorganic Nanostructures: Synthesis, Field‐Emission and Photodetection

AbstractReview: 212 refs.

One-dimensional inorganic nanostructures: synthesis, field-emission and photodetection

One-dimensional inorganic nanostructures have drawn prime attention due to their potential for understanding fundamental physical concepts and constructing nanoscale electronic and optoelectronic devices. This critical review mainly focuses on our recent research progresses in 1D inorganic nanostructures, including their rational synthesis and potential applications, with an emphasis on field-emitter and photodetector applications. Firstly, we will discuss the rational design of synthetic strategies and the synthesis of 1D nanostructures via a vapour phase approach. Secondly, we will present our recent progresses with respect to several kinds of important inorganic nanostructures and their field-emission and photoconductivity characteristics. Finally, we conclude this review with some perspectives/outlook and future research in these fields (212 references).

The use of Reactive Ion Etching for obtaining “free” silica nano test tubes

Silica nano test tubes are one-dimensional inorganic nanostructures with several biotechnological applications including biosensing, magnetic resonance imaging, and targeted cancer therapeutics. They are generally prepared by sol–gel deposition of silica to nanoporous alumina templates. Preparing samples composed of isolated free silica nano test tubes can be a challenging process due to the conformal coating of silica on the template. This causes the formation of a top-surface silica layer which laterally connects the nano test tubes. Herein, we detailed the use of Reactive Ion Etching to remove this top-surface silica layer which yields free silica nano test tubes with template dissolution. Compared with the mechanical polishing approach, Reactive Ion Etching treatment allows a fine manipulation ability of the surface material at the nanoscale level. When used excessively, Reactive Ion Etching causes an orifice closing phenomenon that may be employed to create novel one-dimensional nanocapsules.

Plasma‐Assisted Approaches in Inorganic Nanostructure Fabrication

Plasma is a unique medium for chemical reactions and materials preparations, which also finds its application in the current tide of nanostructure fabrication. Although plasma-assisted approaches have been long used in thin-film deposition and the top-down scheme of micro-/nanofabrication, fabrication of zero- and one-dimensional inorganic nanostructures through the bottom-up scheme is a relatively new focus of plasma application. In this article, recent plasma-assisted techniques in inorganic zero- and one-dimensional nanostructure fabrication are reviewed, which includes four categories of plasma-assisted approaches: plasma-enhanced chemical vapor deposition, thermal plasma sintering with liquid/solid feeding, thermal plasma evaporation and condensation, and plasma treatment of solids. The special effects and the advantages of plasmas on nanostructure fabrication are illustrated with examples, emphasizing on the understandings and ideas for controlling the growth, structure, and properties during plasma-assisted fabrications. This Review provides insight into the utilization of the special properties of plasmas in nanostructure fabrication.

A facile route to self-assembled Hg//MoSI nanowire networks

Nanotechnology crucially depends on new molecular-scale materials with tunable properties. In molecular electronics, building blocks have been reduced to single molecules, while connectors have largely remained at the mesoscopic scale. As a result, the behaviour of such devices is largely governed by interface effects and hence, currently, attention is focused on finding suitable molecular-scale alternatives. In this paper we discuss a new generation of one-dimensional inorganic nanostructures aimed at to replacing the mesoscopic connectors currently used in the electronics industry. We demonstrate how chemical functionalisation of nanowires consisting of molybdenum, sulphur and iodine in conjunction with very low concentrations of molecular mercury leads to one-dimensional systems which can be easily connected opening up new pathways to controlled deposition and interface formation.