Volume 7, Issue 9, September 2016

Internationanl Conference On Nanomaterials And Nanotechnology (ICNANO-2016), India

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 683-683
DOI: 10.5185/amlett.2016.9001

VBRI Press is pleased to announce ‘International Conference on Nanomaterials and Nanotechnology (ICNANO-2016) during 19-21 December 2016. It is a three day international event organised by International Association of Advanced Materials (IAAM) in collaboration with the VBRI Press AB, Sweden. The congress will be held at Vinoba Bhave Research Institute, Allahabad, India. The goal of conference is to provide a global platform for high-tech materials and their manufacturing activities in India. The researchers and engineers coming from academia and industries will be interacted for the advancements of this sector through step towards ‘Make in India’ campaign. 

Rice Husks As A Sustainable Source Of High Quality Nanostructured Silica For High Performance Li-ion battery Requital By Sol-gel Method – A Review

K. Kaviyarasu; M. Jayachandran; M. Maaza; E. Manikandan; J. Kennedy

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 684-696
DOI: 10.5185/amlett.2016.6192

The electronics industry is heavily reliant on the use of silicon in devices ranging from solar panels to circuitry. This is of growing concern due to the environmental impact of sourcing and refining the material. Thus, a green source of silicon is of vital importance to meet the growing demand for silicon in the industry. Rice husk represents an abundant source of nano silica. Currently the husk is considered a waste product that is separated from the grain during the milling process. Several methods have been trailed to extract the nano silica from rice husk. This paper reviews these current methods and presents suggestions of innovative research directions for processing techniques. This work reveals that the structural nature of superfine silica from rice husk ash is independent of the purification method, but dependent on the incineration temperature used. The paper concludes by advocating the physic-chemical process for producing high purity reactive nanosilica from rice husk. This method has the advantage of having high volume production versatility and being environmentally friendly. However, control of the morphology, shape, size, crystalline structure and chemical composition of rice husk nanostructures remains a challenge in the development of 3D nanopores arrays controllable by synthesis methods. We hope this article can provide the reader with snapshots of the recent development and future challenges.

Synthesis Of Nanostructured Tungsten Oxide By Thermal Oxidation Method And Its Integration In Sensor For VOCs Detection

Bhagaban Behera; Sudhir Chandra

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 697-701
DOI: 10.5185/amlett.2016.6101

In this study, tungsten oxide nanorods have been grown by thermal oxidation of tungsten film deposited on oxidized silicon substrates for gas sensing applications. Tungsten film of thickness 100 nm was deposited by sputtering method and thermally oxidized in atmospheric ambient to synthesize nanorods. The morphology and crystal structure of tungsten oxide nanorods were characterized by scanning electron microscopy and X-ray diffraction. Also, crystal structure was verified using Raman techniques. Surface chemical composition of nanorods was analyzed using X-ray photoelectron spectroscopy. Results revealed that 100 nm film of tungsten, oxidized at 450 oC, produces nanorods of WO3 having monoclinic structure with diameter ~100 nm and length up to 1µm. Using standard photolithography process, Au/Cr inter digital electrodes were formed and nanorods were synthesized on it for VOCs sensing application. Sensor incorporating WO3 nanorods exhibits very good response to ethanol, methanol and acetone vapors. The sensor response was studied at different operating temperatures for varying concentration of VOCs. The results suggest the sensor has good potential towards gas sensing applications. It is demonstrated that these sensors can detect upto 10 ppm of ethanol vapour concentration when operated at 100 oC temperature.

Structural, UV-VIS-NIR Luminescence And Decay Associated Spectral Profiles Of Sm3+ Doped Calcium Phosphate Glass

Sooraj H. Nandyala; Ricardo Pires;Rui L. Reis; Graham Hungerford; J. L. Rao; Isabel B. Leonor

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 702-707
DOI: 10.5185/amlett.2016.6244

The present paper reports a calcium phosphate host glass doped with 2 mol% of samarium oxide (2Sm). The glass has been characterized by FTIR, SEM, EDS analysis, and X-ray mapping. Exciting in the visible, using 405 nm and 423 nm, we observed intense, sharp green, yellow, orange emission peaks (4G5/2→6H5/2, 7/2, 9/2) at 560nm, 596 nm and 643 nm respectively. A weak red emission was also observed at 704 nm. Two NIR peaks at 1134nm (4G5/2→6F11/2) and 1310 nm (4G5/2→6F9/2) are monitored by using an excitation at 1060 nm. Furthermore, by making use of time-resolved emission spectroscopy (TRES) measurements, enabled the decay associated spectra to be obtained and the kinetic parameters for the different emission bands to be determined for comparison with steady state emission spectra.

Half Metallic Transition In Silver-adsorbed Zigzag Graphene Nanoribbons

Pankaj Srivastava; Subhra Dhar; Neeraj K Jaiswal

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 708-712
DOI: 10.5185/amlett.2016.6275

We investigate Ag atom bonding to zigzag graphene ribbons and properties of these systems to increase the understanding of spin transport. Results concerning the total energies preferred binding sites, equilibrium distances, and electronic character for Ag adatoms on ZGNR are predicted in this study. The study also provides insight into the diffusion kinetics of adsorbed Ag atoms on zigzag edged graphene nanoribbons. The ribbons considered in the present work have an antiferromagnetic ground state and undergoes transition from semiconducting to half-metallic on spin polarization. DOS profiles of Ag-adsorbed ZGNR at the bridge site reveals low DOS across the Fermi level ensuring its semiconducting character, validated from the unpolarized spin calculations. Though nonlinear at biases less than 1V in the FM and AFM calculations, the spin current of atop adsorbed ribbon increases rapidly with the increase of the bias voltage beyond 1V.

Porous TiNi-based Material And Infrared Radiation In Needle-free Treatment Of Diabetic Patients

Gunther S.V; Dambaev G.Ts; Chekalkin T.L; Kang J-H; Kim J-S; Gunther V.E

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 713-718
DOI: 10.5185/amlett.2016.6037

Despite the prescribed benefits of insulin widely used in treating diabetes, patients still feel the inconvenience and perceived pain related to multiple daily administrations by needle insulin injections. Approved inhaled insulin of the second generation has not so far achieved expectations. Design of needle-free delivery systems for insulin is an active area of research and this paper reports on the development of a new needle-free approach to deliver insulin treating diabetes. Porous TiNi-based alloys serve as high-density materials being capable of holding insulin solutions within the structure of the material, and infrared radiation promotes the directional diffusion of insulin from the TiNi porous structure into the skin. Taking these two facts into account, the needle-free device (NFD) for delivering insulin uses a new porous-permeable TiNi-based material and a novel infrared radiation mediated delivery system. The NFD described causes no skin irritation or lesions and is safe to use in practice. Its efficiency in delivering insulin was clinically assessed on 42 diabetic patients. The results show promising prospects as a new technology for delivering insulin and other liquid drugs.

Synthesis And Characterisation Of Polyaniline (PAni) Membranes For Fuel Cell

Franco D.R. Amado;Satheesh Krishnamurthy

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 719-722
DOI: 10.5185/amlett.2016.6127

Over the past decade or so, alternative energy plays a pivotal role in addressing challenges posed by nature. Polymer electrolyte membrane fuel cell is one of the promising alternative energy and there has been significant research and technological investments done in this field. The key information and future prospective of the field is energy conversion and storage, both of which are essential in order to meet the challenges of global warming and the limited fossil fuel supply. However, polymer membrane in particular plays a crucial role in advancing this technology further. The utilization of conducting polymers in manufacturing membranes combining their electrochemical properties along with mechanical properties is of primary importance to enhance the efficiency of this system. In the present study blends of high impact polystyrene (HIPS) and polyaniline (PAni) were obtained with the aim of producing membranes for fuel cell. HIPS and PAni were dissolved in tetrachloroethylene, a common solvent for both materials. After dissolution, PAni was dispersed in an HIPS polymeric matrix. The membranes were molded on to glass plates using a laminator to keep thickness constant, and the solvent evaporated slowly for 24 h under room temperature. The amount of polyaniline used was 10 and 20 % weight. The electronic and structural properties were carried out using X-ray photoelectron spectroscopy (XPS), Thermogravimetric Analysis (TGA) Raman spectroscopy, Scanning electronic microscopic (SEM). The analysis indicate that PAni incorporation and its dispersion into the polymeric matrix modifies the membranes properties and show improvement in efficiency.

Structural, Corrosion And Mechanical Properties Of Sputtered Deposited Chromium Tungsten Nitride (Cr1-xWxN) Nanocomposite Thin Films

Ravi Prakash; R. Jayaganthan;Davinder Kaur

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 723-729
DOI: 10.5185/amlett.2016.6362

Chromium tungsten nitride (Cr1-xWxN) thin films were successfully deposited on the silicon (100) substrate using dc magnetron reactive co-sputtering. The structural, surface morphological, electrochemical and mechanical properties were studied using X-ray diffraction, field emission-scanning electron microscopy, atomic force microscopy, electrochemical potentiostat and nanoindentation respectively. X-ray diffraction pattern with different atomic concentrations of tungsten (0<x<0.61) shows the presence of (111) and (200) orientation. The content of tungsten (W) in these thin films was controlled by varying the power on the W target. A small amount of tungsten addition led to the significant change in the structural, electrochemical and mechanical properties of the Cr1-xWxN films. The crystallite size varies from 31.1 nm to 15.2 nm with the W content due to variation in nucleation rate and reduction of the self-shadowing effect of the deposition process. Electrochemical properties of these thin films were studied by Tafel polarization curves, which explored the enhancement in corrosion rate due to the higher ratio of real surface area and projected area after a certain amount of W addition. Hardness follows the Hall-Petch relation and tends to increase with the decrease in grain size. Highest hardness 43.18 Gpa and elastic modulus 341.02 Gpa were achieved at the grain size of 15.2 nm in Cr0.48W0.43N thin film. 

Preparation Of High-performance Photocatalytic Core-shell Lamellar Nanostructures ZnO-(Si)-ZnO With high Specific Surface Area

Richard Dvorsky

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 730-734
DOI: 10.5185/amlett.2016.6380

A new preparation method of lamellar core-shell ZnO-(Si)-ZnO nanostructures with high specific surface area and high photocatalytic efficiency is presented in this article. This novel method is based on the application of controlled vacuum sublimation of the frozen liquid dispersion of silicon nanoparticles which were prepared by using the "top-down" process in cavitation Water Jet Mill disintegrator. The particle size of thus disintegrated silicon nanoparticles was measured by dynamic light scattering (DLS). Final product ZnO-(Si)-ZnO was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and amount of ZnO and Si was measured by energy dispersive x-ray spectroscopy (EDAX). Specific surface area was obtained from Brunauer-Emmett-Teller analysis (BET). The photocatalytic activity of ZnO-(Si)-ZnO nanostructure was verified by the decomposition of methylene blue (MB) solution. The Final nanomaterial shows a relatively high specific surface area of 134 m2/g and significantly higher photocatalytic activity compared to standard TiO2 (Degussa P25). Such procedure based on the controlled vacuum sublimation of frozen liquid of suitable metal salts could be a promising method for obtaining photocatalytic nanomaterials with higher specific surface area.

Randomly Oriented Rectangular Shaped Structures Of CuO On NiO/ITO Surfaces

Siddharth Joshi; L. Krishnamurthy; G. L. Shekar

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 735-742
DOI: 10.5185/amlett.2016.6102

Metal oxide materials are one of the promising materials for low power consumption devices due to their unique size and dimensionality dependent physical and chemical properties. Low cost of production is also a key component in micro/nanoscale devices. Cupric oxide (CuO) nanostructures are of particular interest because of their interesting properties and promising applications in solar cells, bio and gas sensors, batteries, super capacitors, catalysis, photo detectors, energetic materials and removal of organic pollutants from waste water. An attempt has been made to synthesize randomly oriented rectangular shaped nanostructures of CuO, via hydrothermal synthesis at low temperature (~70 °C) on top of NiO porous structured film. The film was deposited using chemical bath deposition method at room temperature using ITO coated glass plate as a substrate. One can observe that the CuO growth on NiO/ITO substrate not only filled the porous structures of NiO but also formed the long rectangular shaped nanostructures which were randomly oriented on top of NiO surface. The CuO rectangular nanostructures have the dimensions in order of (6±2.0) μm x (2.0±0.5) μm. The randomly oriented rectangular structure can assist the charge transport in between the different semiconducting layers. These rectangular shaped nanostructures can also be used in nano-electronic devices, or as a p-type conducting wires in future electronic device applications. The present study is limited to the surface morphology studies of the nanostructured thin layers of NiO/CuO composite materials. Structural and absorption measurements of the CuO/NiO hetero junction have been studied using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), UV spectroscopy. The energy band gap of both layers NiO and CuO have been calculated using UV spectroscopy and discussed further. Therefore, the present rectangular structure of CuO could be helpful for the purpose of designing novel function nanostructures for efficient energy harvesting.

Rare Earth Ion Doped Ceria As Electrolytes For Solid Oxide Fuel Cell

K.C. Anjaneya; J. Manjanna; V.M. Ashwin Kumar; H.S. Jayanna; C.S. Naveen

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 743-747
DOI: 10.5185/amlett.2016.6070

We report the nature of rare earth ion doped ceria (REC), Ce0.8Ln0.2O2−δ, (Ln = Y 3+ , Gd 3+ , Sm 3+ , Nd 3+ and La 3+ ) as oxide ion conductors for their plausible application as electrolytes in intermediate temperature solid oxide fuel cell (SOFC). The samples were prepared by citrate-complexation method and characterized by XRD, SEM/ EDX and UV-Visible spectra. The cubic fluorite-type crystal structure is confirmed from XRD patterns, and the observed lattice parameters are in agreement with calculated values. The UV-Vis spectra of the particles dispersed in aqueous medium showed absorption in the UV region which is ascribed to charge-transfer transition. The dc conductivities at 673 K are in the order of Ce0.8Sm0.2O2−δ > Ce0.8Gd0.2O2−δ > Ce0.8Y0.2O2−δ > Ce0.8Nd0.2O2−δ > Ce0.8La0.2O2−δ and their corresponding activation energies are 0.85, 0.87, 0.87, 0.88 and 0.95 eV. Based on ionic and electronic transference numbers, electrical conductivity obtained here is purely ionic, i.e., oxide ion conductors. 

Urchin-like Cobalt Nanostructures For Catalytic Degradation Of Nitro Anilines

Abdul Rauf Khaskheli; Saba Naz; Faruk Ozul; Abdalaziz Aljabour; Sarfaraz Ahmed Mahesar; Imren Hatay Patir; Mustafa Ersoz

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 748-753
DOI: 10.5185/amlett.2016.6264

The undertaken study describes synthesis of urchin-like Cobalt nanostructures (Co NSs) in aqueous solution using gallic acid as both reductant and protecting agent for the catalytic degradation of 4-methyle-2-nitroaniline. UV-Visible (UV-Vis) spectroscopy was used as a primary tool to elaborately study and optimizes the necessary experimental condition for the developed synthetic protocol Fourier transform infrared (FTIR) spectroscopy showed the interaction between gallic acid and the surface of Co NSs via -OH linkages although Scanning electron microscopy (SEM) confirmed the formation of urchin shaped nanostructures with diameter in the range of 80-110 nm and length of tentacles between 1.0 – 1.8 µm. The as-synthesized Co NSs proved to be excellent heterogeneous catalyst for the 100 % reductive degradation of 4-methyle-2-nitroaniline in just 60 sec in presence of reductant (NaBH4) with reaction rate calculated to follow pseudo first order kinetic and rate constant of 0.055s -1 . Furthermore, Co NSs, showed excellent recyclability and were reused four times for the degradation of 4-methyle-2-nitroaniline with efficiency that displayed negligible catalytic poisoning.

Comparative Evaluation Of Ion Exchange Resins And Fibers In Iontophoretic Transdermal Delivery Of Sumatriptan Succinate

Pallavi D. Vispute; Milind P. Wagh; Nazma N. Inamdar

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 754-759
DOI: 10.5185/amlett.2016.6158

Iontophoresis is a convenient and suitable technique for delivering charged sumatriptan succinate (SS) across the skin. The objective of study was to examine the applicability of ion exchange resins and fibers as drug carrier to enhance the efficiency of transdermal iontophoresis. The complexes of drug with cationic resins Indion 204 and Indion 224 (DRC-1, DRC-2) as well as with fibers Smopex 102 and Smopex 101 (DFC-1, DFC-2) were formed by batch method. These complexes were characterized by DSC and PXRD and compared for drug loading, drug release and permeation across rat skin. Effects of constant and pulsed current iontophoresis on drug permeation were also evaluated. The iontophoresis study was conducted using silver–silver chloride electrodes across rat skin. The results suggested that fibers due to their open structure showed more drug loading and release compared to resins. The transdermal flux as well as amount of drug permeated from drug-fiber complexes was higher as compared to that of drug-resin complexes and drug solution. DFC-2 assisted with pulsed iontophoresis at 50 % duty cycle significantly increased the skin permeation of SS and reduced the fluctuation in drug permeation with constant drug delivery compared with the passive controls.

Mesoporous Silica Polymer Nanocomposites Functionalized With Vinyl Pyridine And Vinyl Pyrrolidinone for The Adsorption Of Humic Acid

G. Robin Wilson;Amit Dubey

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 760-764
DOI: 10.5185/amlett.2016.6077

In order to induce the hydrophobicity and the influence of functional vinyl monomers, vinyl pyridine (VP), vinylpyrolidinone (V2P) and vinylsulphonic acid (VSA) were impregnated into SBA-15 matrix to generate SBA/L nanocomposites and characterized for the adsorption of humic acid (HA) for the first time. The structural order of the SBA/L samples was confirmed by standard physicochemical characterizations (powder X-ray diffraction (PXRD), adsorption isotherm, SEM etc). Considerable adsorption (120-140 mg/g) of HA was observed over basic (SBA/VP and SBA/V2P) nanocomposites compared to the acidic ones. Adsorption parameters like effect of temperature, pH, weight of the adsorbent and time were studied. The possible mechanistic pathway for hydrophilic/hydrophobic interactions was also explained.

NUV Excited K2SrP2O7: RE3+ (RE = Sm, Tb, Eu, Dy) Phosphors For White Light Generation 

Ketki S. Dhoble; J. A. Wani; S. J. Dhoble

Advanced Materials Letters, 2016, Volume 7, Issue 9, Pages 765-769
DOI: 10.5185/amlett.2016.6182

Phosphate based compounds doped with rare earth ions are promising luminescent materials for many applications including solid state lighting. In this work photoluminescence properties of K2SrP < sub>2O7:RE 3+ (RE = Sm, Tb, Eu, Dy) phosphors are presented for the first time.  K2SrP < sub>2O7:RE 3+ phosphors activated with the trivalent rare earth ions were synthesized by combustion method. Phosphors were characterized for phase purity, morphology and luminescent properties. Elemental analysis was done through energy dispersive spectroscopy (EDS). The emission and excitation spectra were followed to study the luminescence characteristics of K2SrP < sub>2O7:RE 3+   phosphors. The as prepared powders of RE 3+ doped  K2SrP < sub>2O7 emit red, green and yellowish white light as a result of f-f transitions. The study is novel as no such luminescence data are available for this compound.