Vertically aligned amorphous titania (TiO2) nanotubes are produced by anodizing Ti foils at various applied potentials in a neutral electrolyte solution containing fluoride ions. Pore size and wall thickness are tuned in the range from 30 to 70 nm and 17 to 35 nm, respectively, by adjusting the applied potential, in addition to tuning the tube length from 355 to 550 nm. Utilizing all of these films as negative electrode materials in lithium-ion batteries delivers stable capacities of 130–230 mAh g–1 and 520–880 mAh cm–3 up to 200 cycles. Microstructural analysis shows that there is no structural change or mechanical degradation in the active material, and the amorphous active material maintains good contact with the substrate/current collector. A continuum elasticity model for the tubular geometry is presented to understand the diffusion-induced stresses, fracture tendency, and stability in TiO2 nanotubes. Modeling results indicate that the fracture tendencies of nanotubes with the dimensions in this work are very small; stable reversible capacity retention results from the high ratio of inner to outer diameter of the tubes. In other words, tubes with thinner walls more easily accommodate expansion or contraction during the lithiation/delithiation process. A guideline for designing lithium-ion battery nanotube electrodes is given such that under specific conditions the fracture tendency is small and volumetric charge density is high.

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The applications of microwave processing of electrode materials for Li-ion batteries have been reviewed. This paper intends to insist at the advantages of the microwave processing and its credentials for commercialization. In order to achieve successive commercialization/ industrial application, a systematic understanding of the microwave processing becomes imperative. In the advent of this, an extensive study on the behavior of material in electromagnetic field has been presented. Microwave processing of various materials like lithium cobalt oxide, lithium manganese oxide, lithium nickel oxide, lithium titanium oxide and their derivatives, copper bismuth oxide, antimony sulfide, and tin oxide graphite has been reviewed in detail. Also, the dependence of microwave processing in operating frequency, geometry, preheating, soaking time, susceptor material, and single (or) multimode cavity has been reviewed.

Nitrogen-and oxygen-containing activated carbons have been synthesized from sucrose and ammonium nitrate (AN) by carbonization at different temperatures (600 -900 °C) under a flow of nitrogen gas with steam. A set of carbons have been synthesized without AN. The carbons have been characterized by using X-ray diffractometry (XRD), elemental analysis, solidstate 13 carbon nuclear magnetic resonance (NMR) spectroscopy, X-ray photoelectron spectroscopy (XPS), thermo-gravimetric analysis (TGA), di-nitrogen adsorption-desorption, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. Nitrogen from AN has been found to be incorporated into carbon samples. Electrochemical performances of the carbons have been studied in 1 M sulphuric acid using cyclic voltammetry and galvanostatic charge-discharge cycling. The use of AN favors the formation of carbons with higher surface areas and graphitic nature. One of the carbons with a BET surface area of 518 m 2 g -1 , a nitrogen content of 3 % and an oxygen content of 20.4 % shows a specific capacitance of 277 F g -1 . Carbons obtained using AN show better capacitance than the ones obtained without AN. Higher carbonization temperatures favor the formation of carbon with the higher capacitance values.

The average vapor fluxes, J, across three sets of AAO membranes with average nanochannel diameters (and porosities) centered at 80 nm (32%), 100 nm (37%), and 160 nm (57%) varied by < 25%, while we had expected them to scale with the porosities. Our multiscale simulations unveiled how the high thermal conductivity of the AAO membranes reduced the effective temperature drive for the mass transfer. Our results highlight the limitations of AAO membranes for DCMD and might advance the rational development of desalination membranes.