Materials Science Forum Vols. 830-831

Abstract: Multi-walled carbon nanotube (MWNT) reinforced carbon foams were prepared by thermo-foaming of MWNT dispersions in molten sucrose followed by dehydration and carbonization. The rheological studies showed that the uniform dispersion of MWNT was achieved up to 1.5 wt.%. The carbon foams showed cellular structure. The density of the carbon foams increased with an increase in the MWNT concentration up to 0.25 wt.% and then remained more or less constant. The maximum compressive strength of 4.9 MPa was achieved at the MWNT concentration of 0.5 wt.%.

Abstract: A green low temperature combustion route is proposed for the synthesis of CuO nanoparticles, using Copper nitrate powder and Nigella sativa (Kalonji) seed extract as the starting materials. The formation of CuO Nps was characterized by PXRD, SEM, UV-Visible etc. The PXRD Pattern reveals that as-synthesized CuO Nps of monoclinic phase and Crystallite structure. The scanning electron microscopy (SEM) images reveal the morphology of the nanoparticles are spherical in shape. CuO Nps show significant antibacterial activity against both gram +ve and Gram-ve bacterial strains using agar well diffusion method. The present method brings out a promising green, simple, low cost and low temperature way to prepare multifunctional CuO nanomaterials.

Abstract: Efficient visible light active TiO₂-Molybdenum sulphide (TiO₂-MoS₂) composites were prepared by solvothermal methodfrom titanium isopropoxide and commercial MoS₂ using N-methyl 2-pyrrolidone (NMP) and isopropanol (IPA) solvent mixture. Extended absorption band edge and enhanced visible light absorbance are supplemented intothe TiO₂-MoS₂ composites by this method. While TiO₂ shows ~48% visible light photodegradation of rhodamine B (RhB) the TiO₂-MoS₂(0.24) exhibits~74% of degradation. In addition to the visible light enhancement, very high surface area and reduced charge transfer resistance at the interfaces are attributed to the enhanced activity of the composite.

Abstract: The influence of reactivity of different sheath metals such as Ag, Fe, Cu, Ni and SS on the superconducting properties of NdFeAsO_0.6F_0.4 wires has been investigated. The observed structural and superconducting properties of the metal sheathed wires conclude that among the five candidates Ag and Fe are technically compatible to be used as sheath materials in terms of reactivity. However, the best superconducting properties such as T_C and transport J_C were exhibited by Ag sheathed NdFeAsO_0.6F_0.4 wires.

Abstract: Thermal Protecting System (TPS) material, consisted of silica reinforced fibres and coated with transtion metal complex was exposed to atomic oxygen produced in Electron Cyclotron Resonance (ECR) plasma reactor. The choice of atomic oxygen is based on the necessity of investigating its inteaction with transition metal complex during the re-entry of the space vehicle. The experiments were carried out at different temperature in the range of 30-500°C. The surface morphology of the tile material was investigated with and without exposure to oxygen plasma as a function of temperature using scanning electron microscopy technique, whereas structural analysis of the same samples was carried out using x-ray diffraction technique. Prior to this, ECR plasma reactor was charectorised for electron energy and plasma density using Langmuir probe so as to know the plasma parameter during the interaction.

Abstract: Nickel nanowires were synthesised using a template free chemical method. The phase purity and crystallinity of the synthesized nanowires were studied. Nickel nanowires with diameters of approximately 100-120 nm have exhibited a saturation magnetisation value of 51 emu/g and coercivity of 300 Oe which makes them potential candidates for magnetic sensor applications.

Abstract: The objective of the present study is to fabricate micropatterned polystyrene-alumina nanocomposite (PAN) film by immersing the casted PAN/toluene solution into the bath of a non-solvent of the polymer. Immediate precipitation occurs and creates concavities on the surface of PAN cast after drying due to phase separation induced by solvent non-solvent exchange mechanism assisted by amphiphilic modified alumina particle. PAN film with relatively uniform micropatterns is formed which have the maximum dispersion limit of particles. The effect of particle loading and dispersion on the morphology of pattern is investigated, and a possible mechanism is discussed.

Abstract: A non-aqueous synthesis technique of room temperature curable titania ink, screen printed on flexible BoPET film for printed electronics applications is reported. The phase evolution of rutile titania powder, formulation of a fast curing titania ink, as well as the microstructure and dielectric properties of printed pattern are discussed. In terms of ease of synthesis, cost effectiveness and faster curing time, the developed ink is found to be advantageous over water based dielectric inks.

Abstract: Hydroxyl terminated poly (ethersulfone) was used to modify the surface of multi-walled carbon nanotube (MWCNT). The grafting reaction was confirmed by different characterization techniques such as Fourier Transform Infrared Spectroscopy, Raman Spectroscopy and Transmission Electron Microscope. Epoxy nanocomposites using the modified fillers were prepared. The fracture toughness of the system was examined and compared with MWCNT-epoxy nanocomposite.

Abstract: Graphene oxide incorporated polymer matrix provides a multifunctional facet due to the reinforcing effect of graphene oxide (GO) with wide range of properties. Nanofibers are fabricated by a versatile technique known as electrospinning. The present study demonstrates the fabrication of gelatin, a protein nanofibers non-covalently functionalized with GO. The effect of GO on gelatin nanofibers in terms of mechanical performance is studied. In order to improve the water resistance of the resulting nanofibers, cross-linking is performed using dextran aldehyde.