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Ordered ZnO nanorod (NR) arrays have been prepared on transparent conducting oxide (TCO) substrates by a facile seed-assisted hydrothermal route. The optical properties of the samples were investigated by temperature-dependent photoluminescence (PL) spectra. Two sharp peaks were clearly identified in the ultraviolet (UV) band, located at 3.34 and 3.26 eV in 10 K spectrum, and were labeled as peaks A and B. Both the peaks exhibited different quenching behaviors, although their red-shift characteristics were almost the same with temperature rising. Something gave rise to a possible mechanism to explain such a behavior. Specifically, peaks A and B were assigned to the bound excitons and carrier transitions from shallow donor levels to the valence band, respectively. The detailed analysis will be illustrated in this study. It is hoped that this work could render guided information for understanding the carrier recombination and dynamics behavior in single-crystal ZnO nanostructures.

ZnO with 2D flower-like and 1D rod shape were obtained from simple and rapid hydrolysis of Zn nanopowder. The Zn nanopowders were incorporated into distilled water with acetic acid and then the solution was stirred at 60°C for 8 h. The nanoflower-like and rod shape were formed without any surfactant. It seems that the acetic acid played a role of controlling PH and etching the oxide layer on the surface of metal nanopowders to enhance rapid reaction with distilled water. X-ray diffraction patterns for all samples exhibited that the resultant precipitates were completely transformed to ZnO powder. It is clearly observed that the morphological changes of ZnO with reaction time in aqueous solution follows chestnut bur → flower → tetrahedron → rod sequences during the hydrolysis reaction.

This paper presents an analytical investigation on the buckling and post-buckling behavior of rotating nanorods subjected to axial compression and clamped at both ends. The nonlinear governing equations are derived based on the classical Euler–Bernoulli theory and Eringen's nonlocal elasticity model. The critical load parameters such as angular velocity and compressive axial force are determined for given values of nonlocality parameter. The validity, convergence and accuracy of the solutions are established by comparing them with known classical solutions. The numerical results show that an increase in the nonlocality parameter gives rise to an increase in post-buckling deformation.

The synthesis of novel vanadium dioxide nanorods has been achieved by using V₂O₅ and cetyltrimethyl ammonium bromide (CTAB) in a sol–gel reaction followed by hydrothermal treatment. Morphology and structure of the sample as well as vanadium oxidation state were characterized by XRD, SEM, HRTEM, ESR, XPS and redox titration. The results show that the products are monoclinic (C/2m) B phase VO₂ nanorods and they are 1~2 μm in length. HRTEM micrographs reveal that they indeed form bundles of agglomerated smaller filaments with diameters ranging from 20 to 40 nm besides single nanorod. This filament-like shape in the nanoscale dimension leads to the exposure of a large fraction of the atoms to the surface. Thus, these materials are promising candidates for the development of new functionalized materials. CTAB not only generates a reducing atmosphere, but also plays a key role in the growth of the nanorods. The simplicity of hydrothermal process, as well as cheapness and availability of raw materials are advantages of this method.

Rutile TiO₂ nanorods have been successfully prepared by a sonochemical method. The microstructures of TiO₂ nanorods were investigated in detail by transmission electron microscopy (TEM), selected area electron diffraction (SAED) and high-resolution transmission electron microscopy (HREM). Probable mechanisms for the sonochemical formation of TiO₂ nanorods are proposed.

In this paper, we demonstrate a simple facile aqueous chemical route to prepare large scale Gd doped ZnO nanorod at a temperature of 95°C. X-ray diffraction pattern confirms the wurtzite phase of Gd-doped ZnO nanorods having intense (002) peak with a peak shift towards lower angle. The UV emission intensity decreases by two orders of magnitude and blue-orange broad-band emission emanates from the defects, increases slightly by doping Gd ion in ZnO. Localized SAED patterns taken using nanoprobe size reveals that the nanorods are single crystals grown along c-axis [0001] direction. A systematic evalution of enhancement in ferromagnetism (M = 0.07 × 10^-2 emu/g to 1.4 × 10^-2 emu/g) indicates incorporation of Gd ions into the Zn lattice sites.

The presence of size effects represented by a small nanoscale on torsional wave propagation properties of circular nanostructure, such as nanoshafts, nanorods and nanotubes, is investigated. Based on the nonlocal elasticity theory, the dynamic equation of motion for the structure is formulated. By using the derived equation, simple analytical solutions for the relation between wavenumber and frequency via the differential nonlocal constitutive relation and the numerical solutions for a discrete nonlocal model via the integral nonlocal constitutive relation have been obtained. This results not only show that the dispersion characteristics of circular nanostructures are greatly affected by the small nanoscale and the classical theory overestimates the stiffness of nanostructures, but also highlights the significance of the integral nonlocal model which is able to capture some boundary characteristics that do not appear in the differential nonlocal model.

This paper presents the postbuckled configurations of simply supported and clamped-pinned nanorods under self-weight based on elastica theory. Numerical solution is considered in this work since closed-form solution of postbuckling analysis under self-weight cannot be obtained. The set of nonlinear differential equations of a nanorod including the effect of nonlocal elasticity are investigated. The constraint equation at boundary condition technique is introduced for the solution of postbuckling analysis. In order to solve the set of nonlinear differential equations, the shooting method is utilized, where the set of these equations along with boundary conditions are integrated by the fourth-order Runge-Kutta algorithm. Numerical results are obtained and the highlighting influences of the nonlocal elasticity on postbuckling behavior of nanorods are discussed. The obtained results indicate that the rotation angle and the postbuckled configurations of nanorods are varied by changing the nonlocal elasticity parameter. The effect of nonlocal elasticity shows the softening behavior in comparison with the Euler beam. The present formulation together with constraint boundary condition technique is an effective solution for postbuckling analysis of a nanorod under self-weight including the effect of nonlocal elasticity.

In this research, nanocrystalline titanium dioxide (TiO₂) particles were prepared by a modified alkoxide technique under basic and acidic conditions at room temperatures. A simple method for preparing different morphology of TiO₂ has been developed. The reaction condition was used to control the crystalline size, phase and morphology of the TiO₂ nanostructures. In this process by adjusting the R_w (water to precursor ratio) and pH value the hydrolysis and condensation reactions were controlled. This led to the development of a new process to produce TiO₂ nanorod (for the first time by sol–gel method) at high pH value (basic) while the water content was sufficient whereas at low pH value (acidic) nanosphere TiO₂ were obtained. The powders were characterized by DTA, XRD, FE-SEM and UV–vis techniques and their physical properties were compared.

A new TiO₂ nanoparticles/nanorods composite electrode was fabricated and applied in dye-sensitized solar cells (DSSCs). The TiO₂ nanorods were obtained by grinding the electrospun TiO₂ nanofibers mechanically. The composite photoanode of dye-sensitized solar cells was fabricated by using TiO₂ nanoparticles (P25) and electrospun TiO₂ nanorods. At the optimized condition, the power conversion efficiency (η) based on a triphenylamine dye (SD2) and a ruthenium dye (N719) are 8.28% and 8.80% under AM 1.5 illumination (100 mW ⋅ cm^-2), respectively. The results show that the electrospun TiO₂ nanorods in the composite photoanode improve the physicochemical properties and enhance the photovoltaic performances of solar cells.

Using KOH and WO₃ as raw materials, K₁₀[H₂W₁₂O₄₂]$\cdot$10H₂O nanorod was successfully synthesized via controlling the pH value and the K/W mole ratio of hydrothermal system. The structure and morphology of the samples were characterized by XRD, SEM, TEM, HRTEM and selected area electron diffraction (SAED). The size of K₁₀[H₂W₁₂O₄₂]$\cdot$10H₂O nanorod was about 300nm in width and 3–10$\mu$m in length. The nanorod consisted of self-assembly nanowires with about 10nm in width. Moreover, the electrochemical performance of K₁₀[H₂W₁₂O₄₂]$\cdot$10H₂O as anode material was investigated, indicating that the as-prepared sample electrode possessed a certain ability of lithium ion insertion/extraction, and exhibited a high initial discharge capacity of 310mAh g${}^{-1}$.

The well-defined NaGdF₄:Yb,Er nanorods (NRs) with various aspect ratios were synthesized using a facile hydrothermal method. The morphology and crystal phase of NRs could be controlled by reaction conditions. NaGdF₄:Yb,Er NRs with various aspect ratios could be synthesized and their upconversion (UC) luminescence was tuned. It is displayed that the NRs with aspect ratios about 5 exhibited the strongest UC luminescence among samples. The growth mechanism and morphology transition of NRs had been deduced by schematic diagram. And UC mechanism had been determined by energy level diagrams. Compared with previous reports, the work provided a facial method for UCNRs with various aspect ratios at lower temperature.

LiV₃O₈ nanorod material was prepared by a simple sol–gel method. The electrochemical properties of the as-prepared LiV₃O₈ in 0.5 M Li₂SO₄ aqueous electrolyte were studied through cyclic voltammograms (CV) and discharge–charge measurements. Experiments show that this nanorod material can deliver the capacities of 72, 62 and 53 mAh/g at 20, 50, 100 mA/g, respectively. After 50 cycles, it can maintain 64, 47 and 40 mAh/g, corresponding to 88%, 76% and 77% of the initial capacities, which suggest that this nanorode material presents good cycling performance as anode material for aqueous rechargeable lithium batteries.

Development of non-precious electrocatalysts with applicable electrocatalytic activity towards the oxygen reduction reaction (ORR) is important to fulfill broad-based and large-scale applications of metal/air batteries and fuel cells. Herein, nickel and cobalt molybdates with uniform nanorod morphology are synthesized using a facile one-pot hydrothermal method. The ORR activity of the prepared metal molybdate nanorods in alkaline media are investigated by using cyclic voltammetry (CV), linear sweep voltammetry (LSV) and chronoamperomety in rotating disk electrode (RDE) techniques. The present study suggests that the prepared metal molybdate nanorods exhibit applicable electrocatalytic activities towards the ORR in alkaline media, promising the applications as non-precious cathode in fuel cells and metal–air batteries.

High-efficiency, cost-affordable and environmentally sound catalysts are urgently needed for indoor air purification. Herein, we report the first investigation on room-temperature removal capabilities of AMoO₄ (A = Ni and Co) and derived molybdate–Pt composites with uniform nanorod morphology. The HCHO removal or oxidation capabilities and mechanisms are also compared and rationalized, which, we hope, can form a solid basis for potential applications of molybdate for indoor air purification.

TiNb₂O₇ nanorods have been successfully fabricated by a sol–gel method with a sodium dodecyl surfate (SDS) surfactant. X-ray diffraction indicates that the TiNb₂O₇ nanorods have a Ti₂Nb${}_{10}$O${}_{29}$-type crystal structure. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results show that the nanorods have an average diameter of $\sim$100nm and an average length of $\sim$300nm. As a result of such nanosizing effect, this new material exhibits advanced electrochemical performances in terms of specific capacity, rate capability and cyclic stability. At 0.1C, it delivers a large first-cycle discharge/charge capacity of 337/279 mAh g${}^{-1}$. Its capacities remain 248, 233, 214, 182, 154 and 122mAh g${}^{-1}$ at 0.5, 1, 2, 5, 10 and 20C, respectively. After 100 cycles, its capacity at 10C remains 140mAh g${}^{-1}$ with large capacity retention of 91.0%.

The aqueous colloid of mercapto ligand-functionalized silver nanorod was successfully synthesized by citric acid reduction method. The bigger silver nanospheres were preferably stabilizing in nanorod structure due to the presence of very high concentrations of both silver salts as well as mercapto ligand stabilizer. The properties and stability of the mercapto ligand-functionalized silver nanorod in aqueous colloid was investigated from standard characterizations. These types of surface functionalization silver nanorod conjugated with various biomolecules have been considered as interesting probe in electrochemical bioassay with improved sensitivity, selectivity for biomedical application and clinical analysis purpose.

Schwertmannite (schw) is a common Fe-bearing mineral in the precipitation of mine wastewater and/or steel pickling wastewater. It could be easily converted to goethite and hematite via heating or hydrothermal treatment and could be used as adsorbent to remove contaminants from wastewater. Herein, the spherical schw was converted into erdite nanorod by a simple hydrothermal method with the addition of Na₂S. Schw was spherical particle with a size of 0.4–1.5 $\mu$m. After treatment, it was converted to erdite nanorod particles with 100 nm diameter and 200 nm length. By adding MnO₂ at the $M_{Mn/Fe}$ ratio of 1, erdite nanorod grew radially to 1–1.5 $\mu$m, whereas MnO₂ was reductively dissolved and recrystallized to rambergite. In the absence of Fe, MnO₂ was directly transformed to octahedral alabandite. The product EN-0, prepared without MnO₂, showed the optimal $q_{max}$ of oxytetracycline (OTC, 7479.6 mg/g), which was 12 times that of schw. In OTC-bearing solution, erdite was unstable and automatically hydrolyzed to generate Fe–SH/Fe–OH-bearing flocs, and it exhibited abundant surface functional groups for OTC adsorption. Subsequently, the hydroxyl and amino groups on the side chain of OTC would also be complexed with the Fe–SH group to generate an OTC–Fe–S ligand, in the form of flake-like particles with a smooth surface. The formed Mn-bearing minerals, for example, rambergite and alabandite, also complexed with OTC as OTC–Mn–S ligands to form quadrangular prism with shoulder and length of 10 $\mu$m and 20–100 $\mu$m, respectively. Spherical schw was converted into a well-crystallized erdite nanorod with the addition of MnO₂, and the product showed potential applications in OTC-bearing wastewater treatment.

In this article, ZnO nanorod arrays were successfully prepared on the indium-doped tin oxide (ITO) by electrochemical deposition process in solution of 0.0015M Zn nitrate (Zn (NO₃)₂·6H₂O) and 0.028M methenamine (C₆H₁₂N₄). Morphology of ZnO nanorods were affected by growth condition such as to control current density. The fabricated ZnO nanorods were characterized by field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). And the photovoltaic properties of the ZnO nanorods were evaluated using 1.5 solar simulator.