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One-dimensional (1D) micro- and nanostructured electrode materials with controllable phase and composition are appealing materials for use in lithium-ion batteries with high energy and power densities, but they are challenging to prepare. Herein, a novel ethanol-water mediated co-precipitation method by a chimie douce route (synthesis conducted under mild conditions) has been exploited to selectively prepare an extensive series of manganese-based electrode materials, manifesting the considerable generalizability and efficacy of the method. Moreover, by simply tuning the mixed solvent and reagents, transition metal oxide bars with differing aspect ratios and compositions were prepared with an unprecedented uniformity. Application prospects are demonstrated by Li-rich 0.5 Li2MnO3⋅0.5 LiNi1/3Co1/3Mn1/3O2 bars, which demonstrate excellent reversible capacity and rate capability thanks to the steerable nature of the synthesis and material quality. This work opens a new route to 1D micro- and nanostructured materials by customizing the precipitating solvent to orchestrate the crystallization process. [ABSTRACT FROM AUTHOR]

Using a one-step solution phase approach, the authors have synthesized uniform jingle bell-shaped cobalt mesopheres (550–750 nm) and assembled the mesospheres into long magnetic chains (20–30 μm). All of the cobalt spheres are hollow with ∼40 nm thick shells but each contains an ∼200 nm diameter solid ball. The nano- to mesoscale structures were realized via reaction of CoCl2·6H2O and N2H4·H2O in the presence of polyvinylpyrrolidone (PVP) in an ethylene glycol solution. Magnetic measurements show a coercivity of about 75 Oe with a remnance of 9.6 emu/g at 300 K. We propose a possible mechanism for the formation of the nanoto mesoscale structures. [ABSTRACT FROM AUTHOR]

Abstract: We report on a comparative study of hybrid solar cells based on blends of poly(3-hexylthiophene) (P3HT) and TiO2 nanorods. Two types of ultrathin TiO2 nanorods, linear and branched, have been synthesized for the first time, and surface modified with different dyes before blending with P3HT. Using pristine P3HT as a reference, the short-circuit current and energy conversion efficiency of poly(3-hexylthiophene)/pyridine-HgBrRed-modified branched-TiO2 solar cells were increased by over an order of magnitude, which were also 2–3 times those of the corresponding linear-TiO2 cells. Our results indicate that the branching and the surface dye modification of TiO2 nanorods could effectively facilitate charge transport in the nanostructured network and exciton dissociation at the inorganic/organic interfaces. Thermal treatment of the blend films was found to further increase the efficiency up to 0.16%. [Copyright &y& Elsevier]

Abstract: The arms of CdSe nano-tetrapods can be greatly elongated with the core diameters and arm width unchanged by multiple injections. Room-temperature absorption and photoluminescence (PL) spectra of tetrapods with different arm lengths show that these tetrapods have almost the same core size, which is consistent with the high resolution TEM results. Field emission characteristics show that the onset field required drawing a current density of from CdSe nano-tetrapods with different arm lengths are , , and , respectively, and the field enhancement factors are determined to be about 218, 554, and 946, respectively. Results show that the longer is the arm of the tetrapods, the lower the turn-on field and the higher the field enhancement factor. [Copyright &y& Elsevier]

Since the electrocatalytic activityof layered molybdenum disulfide(MoS2) for hydrogen evolution reaction (HER) closely dependson its exposed edges, the morphology and size of the material arecritically important. Herein, we introduce a novel solvent-evaporation-assistedintercalation method to fabricate the hybrid of alternating MoS2sheets and reduced graphene oxide layers, in which the nanosizeof the MoS2nanosheets can be effectively controlled byleveraging the confinement effect within the two-dimensional graphenelayers. Significantly, the resulting MoS2/reduced grapheneoxide (RGO) composite shows excellent catalytic activity for HER characterizedby higher current densities and lower onset potentials than the conventionalpre-exfoliated RGO supported MoS2nanosheets. Further experimentson the effect of oxidation degree of graphene, the crystallinity ofMoS2, and the exposed active site density on the HER performanceof the MoS2/RGO composites show that there is an optimumcondition for the catalytic activity of HER due to a balance betweenthe numbers of exposed active sites of MoS2and the internalconductive channels provided by graphene. [ABSTRACT FROM AUTHOR]

Abstract: We introduce a photoanode architecture in dye sensitized solar cell comprising building blocks of ZnO nanotetrapods with a mean arm diameter of 40nm and arm lengths of 500–800nm. This photoanode features a decent roughness factor up to 400, good network forming ability and limited electron-hopping interjunctions. Even without calcination, a power conversion efficiency up to 3.27% (under 100mWcm−2) has been achieved at a film thickness of 31.2μm. The avoidance of the calcination step is an outstanding feat for flexible solar cells. We have also employed impedance spectroscopy to interpret the solar cell performance features. [Copyright &y& Elsevier]

Abstract: The development of different morphologies is desired in the field of nano-materials research. Gold is an interesting material for electronic nanodevice among many other potential applications and lots of morphologies have been prepared. However, hollow gold tetrapod has not been reported. In this paper, hollow gold tetrapods were prepared for the first time by using ZnO tetrapods as a template, HAuCl4 as a gold source and ascorbic acid as a reducing reagent. The structure and growth mechanism were investigated and the results show that the hollow gold tetrapods are composed of gold nanoparticles with a mean diameter of about 7.0nm. [Copyright &y& Elsevier]

Abstract: The transition temperatures for the α or β to δ and the δ to liquid phase for α- and β-Bi2O3 nanowires were investigated. We found that there is a size effect for the δ to liquid phase transition but not the α or β to δ phase transition. This is because the δ to liquid phase transition involves bond rupture as well as surface area reduction, whereas the α or β to δ is only solid–solid phase transition, which requires only the reorganization of the bonds. This is the first time the phase transitions of the Bi2O3 nanowires have been investigated and their size effect revealed. [Copyright &y& Elsevier]

Abstract: In this work, two-photon-excited photoluminescence dynamics in ZnS functionalized ZnO nanotetrapods were investigated. Comparing to the bare ZnO nanotetrapods, the emission peaks of the ZnO/ZnS nanotetrapods red-shifted by 5–10nm, and the photoluminescence intensity and lifetime of the ultraviolet exciton radiative transition increased more than 20 times due to the passivation effect of the core/shell structure. [Copyright &y& Elsevier]