Low temperature solvothermal synthesis of ZnO quantum dots

ZnO quantum dots were synthesized via a low-temperature solvothermal process without using surfactants. Heat treatment of ZnCl2 and NaOH solutions in tetra-ethylene glycol at 140°C led to the formation of spherical ZnO nanoparticles consisting of the aggregates of uniform-sized quantum dots. The particle size and morphology were characterized using transmission electron microscopy, dynamic light scattering, X-ray diffraction, and Brunauer–Emmett–Teller gas absorption measurements. It was found that the quantum dots in the particles were single crystals of ZnO of ∼5 nm in diameter having the wurtzite structure. The quantum dots showed quantum size effects even in the agglomerated form. The growth mechanism of this new type of ZnO nanoparticles is proposed.

Controlled synthesis of TiO2 hierarchical nanofibre structures via electrospinning and solvothermal processes : photocatalytic activity for degradation of methylene blue

The present article describes a new titanium oxide‐based (TiO2) photocatalyst that shows promise for acceleration of dye degradation. A hierarchical TiO2 nanostructure comprising nanorods on‐nanofibres has been prepared using a sol–gel route and electrospinning. Calcination of electrospun nanobre mats was performed in air at 500 °C. The TiO2 nanofibre surface was then exploited as a ‘seeding ground’ to grow TiO2 nanorods by a solvothermal process in NaOH. The nanofibres had a diameter of approximately 100 nm while the nanorods were evenly distributed on the nanofibre surface with a mean diameter of around 50–80 nm. The hierarchical nanostructure showed enhanced photocatalytic activity when compared to pure TiO2 nanofibres. This improved efficiency in degrading methylene blue through the photocatalytic process was attributed to the larger specific surface area of the TiO2 nanostructures, as well as high surface‐to‐volume ratio and higher reactive surface resulting in enhanced surface adsorption and interfacial redox reaction.

Gram-scale and template-free synthesis of ultralong tin disulfide nanobelts and their lithium ion storage performances

Ultralong SnS2 nanobelts with a high production yield up to _98% were synthesized via a gram-scale and template-free solvothermal route. The synthetic mechanism of these intriguing ultralong nanobelts was proposed to be from the synergetic effect of the layered CdI2-type structure of SnS2 and surfacemodification of the capping reagent dodecanethiol. The resulting SnS2 nanobelts showed a high specific capacity of 640 mA h g_1 and stable cycling ability (560 mA h g_1 after 50 cycles), which is much better than a graphite anode.

[Al4(OH)2(OCH3)4(H2N-bdc)3]⋅x H2O: A 12-connected porous metal–organic framework with an unprecedented aluminum-containing brick

A new stable aluminum aminoterephthalate system contains octameric building blocks that are connected by organic linkers to form a 12-connected net (see picture). The structure adopts a cubic centered packing motive in which octameric units replace individual atoms, thus forming distorted octahedral (red sphere) and tetrahedral cages (green spheres) with effective accessible diameters of 1 and 0.45 nm, respectively

Synthesis of LiFePO4@carbon nanotube core-shell nanowires with a high-energy efficient method for superior lithium ion battery cathodes

A high-energy efficient method is developed for the synthesis of LiFePO4@CNT core-shell nanowire structures. The method consists of two steps: liquid deposition approach to prepare FePO4@CNT core-shell nanowires and solvothermal lithiation to obtain the LiFePO4@CNT core-shell nanowires at a low temperature. The solution phase method can be easily scaled up for commercial application. The performance of the materials produced by this method is evaluated in Li ion batteries. The one-dimensional LiFePO4@CNT nanowires offer a stable and efficient backbone for electron transport. The LiFePO4@CNT core-shell nanowires exhibit a high capacity of 132.8 mAh g^-1 at a rate of 0.2C, as well as high rate capability (64.4 mAh g^-1 at 20C) for Li ion storage.