Volume 4, Issue 5, May 2013


Editorial

Advanced Materials World Congress (AMWC)

Ashutosh Tiwari

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 327-327
DOI: 10.5185/amlett.2013.5001

We are glad to announce Advanced Materials Word Congress (AMWC, http://www.amwc2013.org/) together with the International Association of Advanced Materials (www.iaamonline.org) and hosted by the Ä°zmir Institute of Technology in the beautiful coastal town ÇeÅŸme, Turkey at Altinyunus Hotel ÇeÅŸme during 16-19 September, 2013. The goal of congress is to provide a global platform for researchers and engineers coming from academia and industry to present their research results and activities in the field of materials science and engineering with a special attention on interdisciplinary research of advanced materials. The conference will provide opportunities for the delegates to exchange their face-to-face novel ideas and experiences with the international experts during plenary & invited talks, oral presentations and poster sessions. We will set up ten sessions with keynote forum, panel discussion and project negotiation. The full article of presentations will be published in the special issue of Advanced Materials Letters.

Correlation Between The Composition And The rate Of Ionic Transport In Perovskites

David L. Fuks; Arnold E. Kiv

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 328-331
DOI: 10.5185/amlett.2012.10432

Anchor Practically applicable approach for the fabrication of ABO3 perovskites with high rates of ionic transport is developed. The ionic transport in perovskites with transition metals at B – site is considered in terms of the theory of coordination compounds. It is shown that the structure of these materials is sensitive to the values of the effective charge of the ions of transition metals (Z * ) and to the electronegativity (χ) of the surrounding cations. The magnitudes of Z * and χ can be varied by choosing the appropriate elements at sites A and B to induce a distortion of the short range order. This leads to reduction of potential barriers for formation and migration of structural defects including oxygen vacancies. In typical perovskites a correlation between the rates of the ionic transport and the estimated values of Z * and χ is found.

Plant Mediated Synthesis Of Gold Nanoparticles Using Fruit Extracts Of Ananas Comosus (L.) (Pineapple) And Evaluation Of Biological Activities

Nagaraj Basavegowda; Agnieszka Sobczak-Kupiec; Dagmara Malina; Yathirajan HS; Keerthi V R; Chandrashekar N; Salman Dinkar; Liny P

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 332-337
DOI: 10.5185/amlett.2012.9423

AnchorPlant mediated synthesis of metallic nanoparticles is an increasing commercial demand due to the wide applicability in various areas such as electronics, catalysis, chemistry, energy, cosmetics and medicine. In the present investigation, synthesis of gold nanoparticles is done by using fruit extracts of Ananas comosus (L.). Nanoparticles were characterized by using UV visible absorption spectra. Their morphology, elemental composition and crystalline phase were determined by scanning electron microscopy, energy dispersive X-ray spectroscopy and selected area electron diffraction. FT-IR analysis was used to confirm the presence of gold nanoparticles in the extracts. The synthesized gold nanoparticles were generally found to be effective as antimicrobial agents against some important human pathogens like E.coli and Streptobacillus sp. which are affecting and cause diseases like food poisoning and rat-bite fever to human beings respectively.

Biosynthesis Of Silver Nanoparticles Using Loquat Leaf Extract And Its antibacterial Activity

Akl M. Awwad; Nida M. Salem; Ammany O. Abdeen

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 338-342
DOI: 10.5185/amlett.2012.11453

This paper reports a rapid and eco-friendly green method for synthesis of silver nanoparticles from silver nitrate solution using loquat leaf extract. Effect the amount of leaf extract, reaction time, silver nitrate concentration and temperature were investigated. Biosynthesized silver nanoparticles (AgNPs) were characterized by X-ray diffraction (XRD), atomic absorption spectroscopy (AAS) and Fourier transform infrared spectroscopy (FT-IR). UV-vis spectroscopy showed that the surface plasmon resonance (SPR) at 425 nm. The structural peaks in XRD pattern and average crystalline size around 18 nm clearly illustrates that AgNPs synthesized by our green method were nanocrystalline in nature with face centered cubic geometry. The antibacterial activity of biosynthesized silver nanoparticles showed effective inhibitory activity against water borne pathogens, Shegella and Listeria bacteria.

Influence Of Zn Concentration On The Size And Optical Properties Of ZnO nanocrystals In Silica Matrix Grown By RF Co-sputter Deposition

V. V. Siva Kumar; Sunil Ojha;D. Kanjilal; F. Singh

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 343-346
DOI: 10.5185/amlett.2012.10437

In the present study we report the influence of variation in amount of Zn on growth and optical properties of thin films of ZnO nanocrystals in silica matrix deposited by rf magnetron co-sputtering with substrate heating at 200 o C. RBS studies indicate change in the concentration of Zn in the films while Raman spectroscopy measurements indicate presence of excess zinc with different concentration. The XRD spectra of the thin films shows the formation of strong ZnO phase nanocrystals with different sizes in different films while the UV-VIS spectra shows variation in the band edge energy of the ZnO nanocrystals for these films. FT-IR spectra of the films show the Zn-O, Zn-O-Si and Si-O-Si vibrational features related to ZnO, Zn2SiO4 and SiOx phases in the films. The results suggest growth of stable ZnO nanocrystals in silica matrix having better phase and optical quality with increase in the Zn concentration in the thin films, which may be useful in optical applications of ZnO.

Characterization And Evaluation Of Nano-sized α-Fe2O3 pigments synthesized Using Three Different Carboxylic Acid

M. F. R. Fouda; M. A. Wahba;M. F. El-Shahat; M. B. ElKholy; S. A. Mostafa; A. I. Hussien

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 347-353
DOI: 10.5185/amlett.2012.9421

AnchorUniform α-Fe2O3 nanoparticles have been prepared by sol gel method using three different carboxylic acids citric, tartaric and succinic acids as chelating agents. The structure and morphology of α-Fe2O3 samples were characterized using (TGA), (XRD), (TEM), (IR) and diffuse reflectance spectroscopy (DRS) techniques. The TEM images revealed that in all cases, the products consisted of 18–25 nm sized particles close to the average crystallite size calculated from XRD data by the Scherrer’s formula. Among the prepared samples, the sample that has the best thermal stability, the smallest particle size and the reddest color is that prepared in presence of tartaric acid. The prepared samples were evaluated as pigments according to the American Society for Testing and Materials (ASTM) standard methods for evaluation of pigments.

Study Of Strontium Doping On The Structural And Magnetic Properties Of YMnO3 ceramics

Radheshyam Rai; M. A.Valente;Andrei L. Kholkin; Indrani Coondoo

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 354-358
DOI: 10.5185/amlett.2012.9428

AnchorStructural and Magnetic properties are investigated for the Sr doped YMnO3 samples with different composition synthesized by a solid state reaction method. Sr doped YMnO3 is the most distorted perovskite of the RMnO3 series (R=rare earths); the observed sinusoidal magnetic structure is in contrast with those exhibited by the less-distorted members, which are commensurate-type antiferromagnetic structures. A typical anti ferromagnetic (AFM) to paramagnetic (PM) phase transition is observed for the sample with concentration x = 0.12 and the Néel temperature (TN) is about 160 K. With decreasing temperature, the sample with x = 0.12 exhibit a magnetic transition from a paramagnetic (PM) to a ferromagnetic (FM) state.

Development Of Nanobiosensor For Urea By Immobilizing Jack Bean Meal Urease On CdS QDs

Bhavani Prasad Nenavathu; Raj Kumar Dutta

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 359-362
DOI: 10.5185/amlett.2012.10446

Semiconductor nanoparticles (NPs) have attracted much attention as a new class of fluorescent probe for many biological applications including biosensors for glucose, cholesterol, cysteine etc., which were based on their size dependent unique electrical and photophysical properties. One of the major challenges in fabricating nanomaterial based biosensor is conjugation of a suitable compound to quantum dots which is preferably selective to the analyte of interest. Here we report our studies on synthesis, characterization and application of jack bean meal urease immobilized on CdS quantum dots (QDs) for sensing of urea. The CdS QDs were synthesized by chemical precipitation method using Mercaptoacetic acid (MAA) for controlling size as well as for imparting functional group for conjugating urease. The urease immobilize on MAA capped CdS nanoparticle was characterized by an array of techniques, like, UV- visible, Fluorescence, XRD, FT-IR and SEM EDAX. The detection capability of urea was studied by fluorescence spectroscopy at an excitation wavelength of λex = 430 nm and emission wavelength of λem= 546 nm. This method was capable to detect urea in the concentration range of 0.1 µM to 1 mM.

The Influence Of Different Synthesis Routes On Thermoluminescence Of CaSO4: Dy, P, Ce Phosphors

J.A. Wani; M.S. Atone; S.J. Dhoble

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 363-367
DOI: 10.5185/amlett.2012.10433

Anchor CaSO4: Dy, P is known for its dosimetric characteristics for a very long time now. In this work we have carried out a comparative study on TL intensity of CaSO4: Dy, P, Ce phosphors using two different wet chemical synthesis routes. Nobody seems to have reported this kind of study on CaSO4: Dy, P, Ce 3+ phosphors and as a result it may be regarded as something new. Phosphors were characterized by scanning electron microscopy, photoluminescence and thermoluminescence techniques. The two methods were found to drastically affect the TL intensity of CaSO4: Dy, P, Ce phosphors. The TL intensity of CaSO4: Dy, P, Ce prepared by co-precipitation method is less by a factor of 204 than the CaSO4: Dy, P, Ce phosphor prepared via acid evaporation method. Moreover, co-doping of P and Ce ions into CaSO4:Dy was observed to enhance the thermoluminescence intensity by a factor of 1.11 than the standard phosphor in case of phosphor prepared via acid evaporation method. Surface morphology resulted through two different synthesis routes was also studied. Structures like broad metal slabs were observed for CaSO4: Dy, P, Ce phosphors using acid evaporation method. We hope that this study may prove very helpful in selecting a preparation method for CaSO4: Dy, RE phosphors especially when better TL properties and good crystal grain size are desired. We also think that acid evaporation method is always a better choice to prepare CaSO4: Dy, RE phosphors than co-precipitation method.

Surface Modification Of Polyanniline Nanofiber Using Silver nanoparticles To Enhance Sensing Properties

Yasir Ali; A. S. Dhaliwal;R G Sonkawade; Vijay Kumar

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 368-372
DOI: 10.5185/amlett.2012.9422

AnchorThe surface of polyaniline nanofibres is modified by silver nano particles using cyclic voltametry (CV). The surface modifications induced by silver particles are confirmed by scanning electron microscopy (SEM), Energy dispersive X-ray analysis (EDX) and Raman spectroscopic techniques. The SEM micrographs show uniform distribution of silver particles on the surface of PANI nano fibers. Presence of silver particles was confirmed by EDX. Structural variations induced after reduction of Ag-metal particles and formation of polaron and bipolarons are studied by Raman spectroscopy.

Microwave Synthesis And Characterization Of Nanocrystalline Mn-Zn Ferrites

Surender Kumar; Tukaram J. Shinde; Pramod N. Vasambekar

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 373-377
DOI: 10.5185/amlett.2012.10429

Powder diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy were used to characterize the spinel structure of nanocrystalline Ferrites with composition Mn1-xZnxFe2O4 (x = 0.2, 0.4, 0.6 and 0.8) prepared by oxalate coprecipitation technique and followed by microwave heating of precursors. Effect of composition on the lattice constant, x-ray density, crystallite size was studied. Crystallite size and x-ray density increases with increase in Zinc content. The face centered cubic spinel structure has undergone deviation from ideality. A correlation exists between splitting of infrared absorption bands and lowering of composition dependent crystalline symmetry. This preparation technique could be used for synthesis of materials which use microwave transparent precursors.

Synthesis Of Lamellar Porous Photocatalytic Nano ZnO With The Help Of anionic Surfactant

Sharda Sundaram Sanjay; Raghvendra S. Yadav; Avinash C. Pandey

Advanced Materials Letters, 2013, Volume 4, Issue 5, Pages 378-384
DOI: 10.5185/amlett.2012.9427

Lamellar porous ZnO has been synthesized at room temperature with the help of anionic surfactant SDS and characterized by XRD, SEM, TEM, PL, UV-Visible and FTIR spectroscopy. In the present investigation, SDS a peculiar surfactant act like a template and catalyses to the self-assembled growth of lamellar structure. Obtained structure is anisotropic lamellar in form with multiple secondary nucleation flaps growing perpendicular to a central lamina with uniform morphology. Photocatalytic activity of as synthesized ZnO on the degradation of bromophenol blue is also studied. The percentage of decolourization of dye was found 84.2% to 77.4% in first 30 min at 431 nm and 590 nm.