Organically modified montimorillonite nanoclay was added to the epoxy and E-glass-epoxy composites. The influence of nanoclay content (varied between 0 to 5wt %) on the relative crosslink density and the fracture toughness of the epoxy matrix was studied. Differential scanning calorimetry (DSC) indicated that the amino functional groups present on the nanoclay react with the epoxy matrix to increase the crosslink density of about 13 and 18% at 3 and 5wt% addition, respectively. The toughness of the epoxy composites increased by 25% at 3wt% addition of nanoclay, whereas, it decreases at 5wt%. Flexural strength and tensile strength of the E-glass-epoxy composites were found to increase by 12% and 11% respectively at 3wt% addition of nanoclay, while at 5wt% addition these properties decreased due to the matrix embrittlement. Interestingly matrix embrittlement is found to be beneficial in increasing the impact resistance due to spallation of embrittled matrix that ensures the dissipation of the impact energy. 5wt% nanoclay addition increases the impact strength by 29% and reduces the back face bulge of composite by 31%. These results may lead to the design and realization of glass-epoxy composites with better impact strength.design and realization of glass-epoxy composites with better impact strength.

This work was aimed to design efficient catalysts for N 2 O decomposition at low temperatures. Cobalt oxide (Co 3 O 4) was prepared by hydrothermal, precipitation and combustion methods and tested for N 2 O decomposition. It was found that the catalysts prepared by solution combustion synthesis were most active for this reaction. Subsequently, a series of ceria (CeO 2) supported Co 3 O 4 catalysts (xCeCo) were prepared by solution combustion method and used them for N 2 O decomposition. All the catalysts were characterized by analytical methods like XRD, TEM, BET, XPS, UV-Vis, Raman and H 2-TPR. It was found that 10 and 20 wt..% loading of CeO 2 on Co 3 O 4 promoted the activity of Co 3 O 4 towards N 2 O decomposition, whereas, higher loading of CeO 2 reduced the activity. Typical results indicated that addition of CeO 2 increases the surface area of Co 3 O 4 , and improves the reduction of Co 3+ to Co 2+ by facilitating the desorption of adsorbed oxygen species, which is the rate-determining step for the N 2 O decomposition over Co 3 O 4 spinel catalysts. Optimal CeO 2 loading can increase both dispersion and surface area of Co 3 O 4 catalysts and weaken the CoO bond strength to promote N 2 O decomposition.

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Carbon nanofibers (CNFs) are plasma etched by using cold plasma of helium and air for different time durations. Changes in surface characteristics of CNFs due to plasma treatment was studied with Raman spectroscopy, BET surface area analyzer, and atomic force microscopy (AFM). Raman spectroscopic studies showed that, plasma treatment is imparting enhanced degree of disorder for CNFs. While AFM studies indicated enhancement in the surface roughness due to plasma treatment. Laminated (2D) carbon fiber reinforced epoxy matrix (C-epoxy) composites were fabricated with the addition of 0.5 wt% of plasma-etched CNFs and evaluated the mechanical properties of the prepared composites. Results indicate that, plasma-etched CNFs can improve the mechanical properties of CFRPs significantly as compared to untreated CNFs.

A lithium–selenium (Li‐Se)‐alkali activated carbon hybrid cell with a tungsten oxide interlayer is implemented for the first time. The Se hybrid at a Se loading of 70 % in the full Li–Se cell delivers a large reversible capacity of 625 mA h gSe−1, in comparison with 505.8 mA h gSe−1 achieved for the pristine Se cell. This clearly shows the advantage of the carbon in improving the capacity of the Li‐Se cell. A tungsten oxide interlayer is drop‐cast over the battery separator to further circumvent the issues of polyselenide dissolution and shuttle, which cause severe capacity fading. The oxide layer conducts Li ions, as evidenced from the Li‐ion diffusion coefficient of 4.2×10−9 cm2 s−1, and simultaneously blocks the polyselenide crossover, as it is impermeable to polyselenides, thereby reducing the capacity fading with cycling. The outcome of this unique approach is reflected in the reversible capacities of 808 and 510 mA h gSe−1 achieved for the Li‐oxide@separator/Se‐alkali activated carbon cell before and after 100 cycles, respectively, thus demonstrating that carbon and oxide can efficiently restrict the capacity fading and improve the performances of Li‐Se cells.

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