Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Centre for Nanotechnology Research

ZnO/Graphene nanocomposites (ZnO/G) were prepared through a solvothermal route employing ethylene glycol both as a solvent and reducing agent. The ZnO nanoparticles produced were decorated on the surfaces of graphene sheets as seen from the FE-SEM images. The composites were characterized by DRS-UV-Vis spectrum, X-ray diffraction studies (XRD) and field emission scanning electron microscopy (FE-SEM). Furthermore, the as-prepared graphene-based nanocomposites show an excellent photocatalytic activity towards the photodegradation of methylene blue dye. Copyright © 2013 American Scientific Publishers. All rights reserved.

VIT Unitversity

Mechanical

School of Mechanical Engineering

Chennai Campus

Vellore Campus

Nanoscience and Nanotechnology Letters

Solvothermal Preparation of ZnO/Graphene Nanocomposites and Its Photocatalytic Properties

Model photocatalysts composed of TiO2-graphene nanocomposites are prepared to address the effect of graphene quality on their photocatalytic performance. Graphene is synthesized by catalyst-assisted chemical vapor deposition (CVD), catalyst-free CVD and solution processing methods. TiO 2 is prepared by reactive magnetron sputtering and subsequent annealing. Fabricated model photocatalysts have different morphology and physical properties, as revealed using spectrophotometry, atomic force microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, photoluminescence, and four-probe electrical measurements. All graphene-containing composites have significantly higher photocatalytic activity compared to bare TiO2 films in the gas phase methanol photooxidation tests. Their activity is proportional to the electrical conductivity and surface roughness of the respective carbon structure, which in turn depends on the preparation methods. The mechanisms of enhancement are further assessed by comparison with the performance of reference TiO2-graphitic-carbon and TiO2-Au thin films. This journal is © 2013 the Owner Societies.

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Physical Chemistry Chemical Physics

Influence of graphene synthesizing techniques on the photocatalytic performance of graphene-TiO2 nanocomposites

We demonstrate a simple and effective approach to control the diameter of ultrathin ZnO nanowires with high aspect ratios and high densities over large areas. Diblock copolymer-based nanoparticle arrays exhibiting a high degree of hexagonal order and offering easy control of particle size (typically 1–10 nm) and interparticle spacing (25–150 nm) are utilized as nanocatalysts for the subsequent growth of semiconductor nanowires. The as-grown ZnO nanowires exhibit a single crystal hexagonal wurtzite structure and grow along the [0002] direction. Facetted catalyst particles were observed at the tip of the nanowires after synthesis, thus suggesting a catalyst-assisted vapor–solid–solid (VSS) rather than a vapor–liquid–solid (VLS) growth mechanism, the latter being frequently used in semiconductor nanowire production. Such a growth process allows us to easily prepare ultrathin ZnO nanowires with tunable diameters well below 10 nm by taking advantage of the inherent size control of the micellar method during deposition of the catalyst nanoparticles. Raman spectroscopy reveals a phonon confinement effect as the diameter of nanowires decreases. Photoluminescence spectra of these ultrathin nanowires indicate a blue shift of the free excitons and their phonon replicas by 37 meV induced by quantum confinement. © 2013 The Royal Society of Chemistry.

Nanoscale

Controlled synthesis of ultrathin ZnO nanowires using micellar gold nanoparticles as catalyst templates

In this article, we describe a novel straightforward method for the specific identification of viable cells (macrophages and cancer cell lines MCF-7 and Jurkat) in a buffer solution. The detection of the various cell types is based on changes of the heat transfer resistance at the solid-liquid interface of a thermal sensor device induced by binding of the cells to a surface-imprinted polymer layer covering an aluminum chip. We observed that the binding of cells to the polymer layer results in a measurable increase of heat transfer resistance, meaning that the cells act as a thermally insulating layer. The detection limit was found to be on the order of 104 cells/mL, and mutual cross-selectivity effects between the cells and different types of imprints were carefully characterized. Finally, a rinsing method was applied, allowing for the specific detection of cancer cells with their respective imprints while the cross-selectivity toward peripheral blood mononuclear cells was negligible. The concept of the sensor platform is fast and low-cost while allowing also for repetitive measurements. © 2013 American Chemical Society.

ACS Applied Materials and Interfaces

Selective identification of macrophages and cancer cells based on thermal transport through surface-imprinted polymer layers

Materials

Effect of the Milling Time of the Precursors on the Physical Properties of Sprayed Aluminum-Doped Zinc Oxide (ZnO:Al) Thin Films

Cus Nanostructures Have Been Successfully Prepared from Copper Chloride with Two Different Sulfur Sources Like Thiourea and Sodium Thiosulphate by Hydrothermal Route at 150oC. The Growth of Cus Nanostructures Were Investigated for Different Reaction Time Periods of 5 Hrs and 24 Hrs Respectively Using Water as Solvent. the as-Synthesized Cus Nanostructures Are Characterized by X-Ray Diffraction (XRD) and Field-Emission Scanning Electron Microscopy (FE-SEM). XRD Pattern Indicates that the Prepared Cus Nanomaterials Are in Pure Hexagonal Phase. Results Show that Cus Nanomaterials with Different Hierarchical Structures Like Urchins, Nanoplates Etc,. Were Obtained at Different Experimental Conditions. A Systematic Investigation of the Final End Products Has Been Done to Elucidate the Formation Mechanism at Different Experimental Parameters. The Optical Properties of the Cus Structures Were Studied by UV-Vis Absorption Analysis, which Showed Broad Absorption in the Visible Region. The Optical Band Gap of the Cus Nanomaterials Were Found as 2.2 Ev and 2.18 Ev for Different Sulfur Sources.

Journal of Nano Research

Hydrothermal Synthesis of CuS Nanostructures with Different Morphology

Journal of Laboratory Automation

PSoC-Based Embedded Design and Quartz Tuning Fork for Low-Temperature Measurement System Design

A microwave reduction route was employed for the synthesis of Pt nanoparticles supported on multi-walled carbon nanotubes (MWCNT). The as-prepared Pt-MWCNT electrocatalysts were characterized by FT-IR, XRD and TEM analysis. Further, the as-prepared catalysts were probed for its electrocatalytic activity towards methanol oxidation by cyclic voltammetry (CV) in 0.5 M CH3OH + 0.5 M H2SO4 solution. Two kinds of electrocatalysts viz. Pt-MWCNT and Pt-MWCNT/PANI were probed to study the effect of both carbon nanotubes and polyaniline (PANI) towards methanol oxidation. The effect of scan rate, concentration and long-term cycle stability analysis has been investigated in detail. Results show that the presence of MWCNT and PANI improves the electrocatalytic efficiency towards methanol oxidation. Pt-MWCNT/PANI shows high peak current density towards methanol oxidation and good long-term stability even after 600 cycles indicating that the catalyst could be used for practical applications. © 2012, The Author(s).

Applied Nanoscience

Carbon nanotubes and polyaniline supported Pt nanoparticles for methanol oxidation towards DMFC applications

Micro fabricated cantilever beam smart immunosensor was modeled using "Intellisuite" software to detect nanogram level antigen. The FEM simulations were carried out with immunoglobulin antibody, IgG for the detection of C -reactive protein. The effect of geometry of the cantilever beam with different number of holes and thickness of Si piezo resistive-patch on the sensor performance and signal transduction was studied. The effect of nature of Si and CNT piezo resistive-patch on the sensor performance was also investigated. Considering the response of stress and sensitivity, CNT piezo resistive patch is more suitable for the development of smart sensor. A cantilever beam immunosensor 100 μm long, 50 μm wide and 2.4 μm thick with one hole 3 μm long and 6 μm wide in the beam and CNT piezo-patch 100 nm thick is a more promising system for the fabrication for the detection of C -reactive protein. The modeled sensor can detect CRP even at a low concentration of 11.0 ng/ml.