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A visible light active photocatalyst, Ag/TiO 2 /MWCNT was synthesized by loading of Ag nanoparticles onto TiO 2 /MWCNT nanocomposite. The photocatalytic activity of Ag/TiO 2 /MWCNT ternary nanocomposite was evaluated for the degradation of methylene blue dye under UV and visible light irradiation. Ag/TiO 2 /MWCNT ternary nanocomposite exhibits (~9 times) higher photocatalytic activity than TiO 2 /MWCNT and (~2 times) higher than Ag/TiO 2 binary nanocomposites under visible light irradiation. The enhancement in the photocatalytic activity is attributed to the synergistic effect between Ag nanoparticles and MWCNT, which enhance the charge separation efficiency by Schottky barrier formation at Ag/TiO 2 interface and role of MWCNT as an electron reservoir. Effect of different scavengers on the degradation of methylene blue dye in the presence of catalyst has been investigated to find the role of photogenerated electrons and holes. Simultaneously, the Ag/TiO 2 /MWCNT shows excellent photocatalytic stability. This work highlights the importance of Ag/TiO 2 /MWCNT ternary nanocomposite as highly efficient and stable visible-light-driven photocatalyst for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Metal oxide as a thermoelectric material has shown great attention in recent years due to its outstanding thermal and chemical stability, good oxidation resistance, low cost, etc. This article reports the successful synthesis of tungsten oxide (WO 3) nanoparticles and tungsten oxide-reduced graphene oxide (WO 3 -rGO) nanocomposites and studies of their thermoelectric properties. The structural characteristics of the WO 3 nanoparticles and WO 3 -rGO nanocomposites were examined using XRD and Raman techniques. At 313 K, WO 3 -rGO nanocomposites exhibit an ~ 8.8 times enhancement in the thermoelectric material figure of merit (zT). These excellent performances are further supported by up to ~ 13.7 times enhanced electrical conductivity and a ~ 56% reduction in thermal conductivity compared to WO 3 nanoparticles. It has been concluded that reduce graphene oxide helps in forming a conducting pathway in the WO 3 -rGO nanocomposites, allowing the easy passage of charge carriers in the matrix. [ABSTRACT FROM AUTHOR]

Bi 2 Te 3 –MWCNT nanocomposite has been synthesized by hydrothermal technique and demonstrate the role of MWCNT for thermoelectric properties. Herein, MWCNT has been used as conducting filler, which leads to the enhancement in the electrical conductivity in the case of nanocomposite. Bi 2 Te 3 –MWCNT nanocomposite shows ~22% decrease in the thermal conductivity as compared to Bi 2 Te 3 nanostructures, which is attributed to the enhanced phonon scattering at the interfaces of Bi 2 Te 3 –MWCNT nanocomposite. Due to the increase in the electrical conductivity and decrease in the thermal conductivity, the overall enhancement in the figure of merit is ~45% in Bi 2 Te 3 –MWCNT nanocomposite as compared to Bi 2 Te 3 nanostructures. [ABSTRACT FROM AUTHOR]

Introduction of artificial pinning centres in different morphology is a beneficial way to improve the flux pinning properties of a YBCO compound. In the present study, we report the effect of addition of sodium niobate (NaNbO 3) nanostructures in two different form i.e. nanorods (NRs) and nanoparticles (NPs) with a varied wt% (0, 0.5, and 1 wt%) on the pinning capabilities of bulk YBCO polycrystalline samples. The orthorhombic crystal structure of YBCO was confirmed by the XRD spectra even in the nanocomposite samples. The existence of NPs or NRs on the surface and between the superconducting grains of YBCO was confirmed by morphological analysis. The critical temperature (T c) remains almost unchanged as compared to pure YBCO on addition of NaNbO 3 nanostructure in YBCO compound upto 1 wt% concentration. Even at higher fields (upto 6 T) and higher temperatures (upto 75 K), the addition of NaNbO 3 NPs or NRs in YBCO nanocomposite resulted in a significant increase of ~2.6 times in the critical current density as compared to pure YBCO. In comparison to NRs added YBCO nanocomposite samples, NPs added YBCO nanocomposite samples showed higher improvement. Throughout the entire investigated range of applied field, the maximum pinning force was found for 0.5 wt% NPs added composite sample. [ABSTRACT FROM AUTHOR]

A superhydrophobic coating material (PA-ZnO) with a static water contact angle (WCA)>160° has been synthesized by modifying zinc oxide (ZnO) nanoparticles with room temperature stable palmitic acid (PA). ZnO nanoparticles (size ~ 24 nm) with hexagonal wurtzite structure are prepared by hydrothermal method. FTIR study and TEM images confirms the grafting of palmitic acid on ZnO surface. This superhydrophobic nature of PA-ZnO has been attributed to the grafting of palmitic acid on ZnO surface which is confirmed by conducting the WCA measurement of PA-ZnO samples after heating at different temperatures. Surface morphology and roughness were observed as a function of temperature and it was observed that films morphology is changing to smoother films with low air entrapment for higher temperatures. On the same time the root mean square roughness (Rrms) is also reducing. It is observed that the superhydrophobic nature of PA-ZnO nanoparticles reduces with heating at higher temperatures and surface became like hydrophilic for heating temperature of ~ 230 °C. The decrease in the WCA is attributed to the thermal decomposition of palmitic acid from ZnO surface and the same has been confirmed by thermal analysis of PA and PA-ZnO samples. [ABSTRACT FROM AUTHOR]