Time filter

Source Type

Patent
CMET - Photonics And Advanced Materials Laboratory | Date: 2016-05-12

The present disclosure relates to piezoelectric compositions of Formula I comprising Lead ZirconateLead Titanate solid solution. The disclosure further relates to a method of obtaining said composition, method of preparing/fabricating piezoelectric component(s) and piezoelectric component(s)/article(s) obtained thereof. The piezoelectric composition and articles of the present disclosure show excellent electromechanical characteristics along with very large insulation resistance (IR).


Tomer V.K.,D. C. R. University of Science and Technology | Adhyapak P.V.,CMET - Photonics And Advanced Materials Laboratory | Duhan S.,D. C. R. University of Science and Technology | Mulla I.S.,CMET - Photonics And Advanced Materials Laboratory
Microporous and Mesoporous Materials | Year: 2014

Ag nanoparticle loaded mesoporous silica SBA-15 nanocomposites have been synthesized by a facile hydrothermal route with (C2H 5O)4Si in the presence of (AgNO3). Their response towards humidity has been studied. Low angle X-ray diffraction (XRD), Fourier Transform infrared spectroscopy (FTIR), N2 adsorption-desorption, High Resolution Transmission Electron Microscopy (HRTEM), Scanning electron microscopy (SEM) and Energy Dispersive X-ray (EDX) spectroscopy techniques were utilized to characterize the composition and structure of the samples. In comparison with pure SBA-15, the Ag-loaded SBA-15 exhibits improved humidity response within the relative humidity (RH) range of 11-92%. The optimal result were obtained for 5 wt% Ag-loaded SBA-15 sample, which demonstrate an excellent linearity, small hysteresis and high humidity sensitivity; moreover, it also exhibits satisfactory response and recovery time. The resistance shows change of more than 5 orders in magnitude over the entire humidity range. The mechanism for humidity sensing was studied. The investigation of humidity sensing characteristics of Ag-doped SBA-15 sensors indicates that the material has promising application as humidity sensor. © 2014 Elsevier Inc. All rights reserved.


Bauskar D.,North Maharashtra University | Kale B.B.,CMET - Photonics And Advanced Materials Laboratory | Patil P.,North Maharashtra University
Sensors and Actuators, B: Chemical | Year: 2012

This work reports humidity sensing properties of ZnSnO 3 cubic crystallites synthesized by a hydrothermal method. ZnSnO 3 cubic crystallite film exhibits excellent humidity sensing characteristics such as fast response time (∼7 s), rapid recovery (∼16 s), linearity, hysteresis within 3.5%, excellent repeatability, good stability and broad range of operation (11-97% RH). The application of ZnSnO 3 cubic crystallites for construction of humidity sensors is demonstrated. © 2011 Elsevier B.V. All rights reserved.


Danai-Tambhale S.D.,Annasaheb Magar Mahavidyalaya | Adhyapak P.V.,CMET - Photonics And Advanced Materials Laboratory
International Journal of Pharma and Bio Sciences | Year: 2014

In this study, the biosynthesis of silver nanoparticles was carried out by using Psoralea corylifolia L. (family Leguminosae) as reducing agent. As per our knowledge, this is the first report where Psoralea corylifolia seed extract was found to be suitable for the green synthesis of silver nanoparticles. Synthesis of silver nanoparticles was confirmed on the basis of UV-Vis Spectrometer which showed a peak between 400 nm to 440 nm. The synthesized silver nanoparticles were characterized by X-ray diffraction analysis (XRD), Field emission scanning electron microscopy (FE-SEM), and particles size distribution analysis. The biosynthesized silver nanoparticles have been evaluated in vitro for antimicrobial activities and found to have higher antimicrobial activities.


Apte S.K.,CMET - Photonics And Advanced Materials Laboratory | Garaje S.N.,CMET - Photonics And Advanced Materials Laboratory | Valant M.,University of Nova Gorica | Kale B.B.,CMET - Photonics And Advanced Materials Laboratory
Green Chemistry | Year: 2012

It is renowned that the oil refineries are venting off 15-20% H 2S and hardly 5% has been utilized to produce sulphur and water ubiquitously by the Claus process. This process is un-economical, highly polluting and by-products create further acute environmental problems. Here, we have demonstrated the significant approach of the conversion of poisonous H 2S into H2 by stable orthorhombic QD-CdS-glass nanosystems using a most abundant solar light energy source. This is an eco-friendly process that produces cheaper hydrogen as well as degrades organic dyes efficiently. We have investigated a novel, Q-CdS (highly mono-dispersed) germanate glass nanocomposite. Surprisingly, the CdS quantum dots (QDs) obtained in the glass matrix are orthorhombic in structure and highly thermally stable. Generally, the orthorhombic CdS powder is in a metastable state i.e. unstable at normal conditions. The quantum dots of 4-14 nm size of CdS were grown for the first time in the germanate glass. The confinement of orthorhombic CdS was studied using UV-Vis spectroscopy and photoluminescence. There is a drastic change in the band gap of glass without CdS nanocrystals (3.16 eV) as compared to the glass with orthorhombic CdS QDs (2.25 eV). Considering the suitable band gap of the CdS quantum dot-glass for the visible light absorption, the studies of the photocatalytic activity for H2 generation and dye degradation was performed under visible light irradiation for the first time. High H 2 evolution, i.e. 3780 μmol h-1, was obtained, which is much higher than earlier reported for CdS nano-powder. More significantly, the catalyst is stable and easily regenerated as compared to other normal catalysts. The glass nanocomposite also showed excellent methylene blue degradation under visible light irradiation. Such orthorhombic QD-CdS-glass nanocomposites have great significance because they have potential applications in solar cell, LED and other optoelectronic devices. © 2012 The Royal Society of Chemistry.


Bhirud A.P.,CMET - Photonics And Advanced Materials Laboratory | Sathaye S.D.,759 83 Deccan Gymkhana | Waichal R.P.,CSIR - National Chemical Laboratory | Nikam L.K.,CMET - Photonics And Advanced Materials Laboratory | Kale B.B.,CMET - Photonics And Advanced Materials Laboratory
Green Chemistry | Year: 2012

We have investigated an economical green route for the synthesis of a p-type N-doped ZnO photocatalyst by a wet chemical method. Significantly, hazardous H2S waste was converted into eco-friendly hydrogen energy using the p-type N-doped ZnO photocatalyst under solar light, which has previously been unattempted. The as-synthesized p-type N-doped ZnO shows a hexagonal wurtzite structure. The optical study shows a drastic shift in the band gap of the doped ZnO in the visible region (3.19-2.3 eV). The doping of nitrogen into the ZnO lattice is conclusively proved from X-ray photoelectron spectroscopy analysis and Raman scattering. The morphological features of the N-doped ZnO are studied from FESEM, TEM and reveal particle sizes to be in the range of ∼4-5 nm. The N-doped ZnO exhibits enhanced photocatalytic hydrogen generation (∼3957 μmol h-1) by photodecomposition of hydrogen sulfide under visible light irradiation, which is much higher as compared to semiconductor metal oxides reported so far. It is noteworthy that a green catalyst is investigated to curtail H2S pollution along with production of hydrogen (green fuel) using solar light, i.e., a renewable energy source. The green process investigated will have the potential to synthesize other N-doped metal oxides. © 2012 The Royal Society of Chemistry.


Etacheri V.,Bar - Ilan University | Roshan R.,CMET - Photonics And Advanced Materials Laboratory | Kumar V.,CMET - Photonics And Advanced Materials Laboratory
ACS Applied Materials and Interfaces | Year: 2012

Magnesium-doped ZnO (ZMO) nanoparticles were synthesized through an oxalate coprecipitation method. Crystallization of ZMO upon thermal decomposition of the oxalate precursors was investigated using differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques. XRD studies point toward a significant c-axis compression and reduced crystallite sizes for ZMO samples in contrast to undoped ZnO, which was further confirmed by HRSEM studies. X-ray photoelectron spectroscopy (XPS), UV/vis spectroscopy and photoluminescence (PL) spectroscopy were employed to establish the electronic and optical properties of these nanoparticles. (XPS) studies confirmed the substitution of Zn 2+ by Mg 2+, crystallization of MgO secondary phase, and increased ZnO bond strengths in Mg-doped ZnO samples. Textural properties of these ZMO samples obtained at various calcination temperatures were superior in comparison to the undoped ZnO. In addition to this, ZMO samples exhibited a blue-shift in the near band edge photoluminescence (PL) emission, decrease of PL intensities and superior sunlight-induced photocatalytic decomposition of methylene blue in contrast to undoped ZnO. The most active photocatalyst 0.1-MgZnO obtained after calcination at 600 °C showed a 2-fold increase in photocatalytic activity compared to the undoped ZnO. Band gap widening, superior textural properties and efficient electronhole separation were identified as the factors responsible for the enhanced sunlight-driven photocatalytic activities of Mg-doped ZnO nanoparticles. © 2012 American Chemical Society.


Chaudhari N.S.,CMET - Photonics And Advanced Materials Laboratory | Warule S.S.,CMET - Photonics And Advanced Materials Laboratory | Kale B.B.,CMET - Photonics And Advanced Materials Laboratory
RSC Advances | Year: 2014

In the present investigation, a surfactant-assisted hydrothermal route has been employed to design self-assembled rose and hollow marigold-like ZnIn 2S4 flowers. In the absence of the surfactant, uniform (∼3-5 μm) marigold-like flowers are observed. The self-alignment of the transparent petals (∼3-5 nm thick with a length of ∼25-100 nm) leads to the formation of hollow marigold-like flowers, for which a plausible growth mechanism has also been proposed. Moreover, DEA assisted ZnIn2S 4 demonstrates a rose flower-like via self assembly of hexagonal nanoplates. Structural and optical characterization shows the existence of hexagonal structures with a band gap in the range of ∼2.4-2.6 eV. Considering the ideal band gap in the visible region, we have used such unique nanostructured self assemblies of ZnIn2S4 as photocatalysts and demonstrated visible light-driven photocatalytic production of clean hydrogen by toxic hydrogen sulphide, which is abundantly available as a waste gas from oil refineries (15-20%). We believe that continuous efforts in this direction may open up new insights into the design of controllable nanostructures and their potential applications in advanced fields. © 2014 The Royal Society of Chemistry.


Joseph S.,CMET - Photonics And Advanced Materials Laboratory | Phatak G.J.,CMET - Photonics And Advanced Materials Laboratory
Materials Science and Engineering B: Solid-State Materials for Advanced Technology | Year: 2010

We have developed a methane sulfonic acid (MSA) based ternary electrodeposition bath for the deposition of near eutectic Sn-Ag-Cu films aimed at solder bumping applications in electronics. The bath contains thiourea as chelating agent and iso-octyl phenoxy ethanol (OPPE) as surfactant. We added gelatin to this bath and studied its effect on bath stability, microstructure of the deposited films and the film composition. It is found that the bath containing both the additives, viz. OPPE and gelatin, show improved stability up to 8-10 days. Striking improvement in the film microstructure, in terms of the compactness, uniformity and refinement of grains was found when the bath contained these additives. Detailed electrochemical studies with the help of cyclic voltametry and impedance analysis helped in understanding the role played by these additives during deposition. It is confirmed that there is a formation of loosely connected, highly non-uniform passivating film on the cathode surface, which is removed competitively by the depositing metal ions during the deposition. It is also clear that the additives play a role in the formation of such a passivating film. © 2010 Elsevier B.V. All rights reserved.


Bamsaoud S.F.,University of Pune | Rane S.B.,CMET - Photonics And Advanced Materials Laboratory | Karekar R.N.,University of Pune | Aiyer R.C.,University of Pune
Sensors and Actuators, B: Chemical | Year: 2011

SnCl2 (solution) was spin coated on soda lime glass and Al 2O3 substrate to obtain nano-particulate tin oxide film, directly by sintering at 550 °C for 40 minutes (min). The surface morphology and crystal structure of the tin oxide films were analyzed using atomic force microscopy (AFM) and X-ray diffraction (XRD). The size of SnO2 nanostructure was determined from UV-vis and found to be ≲3 nm. These films were tested for sensing H2 concentration of 0.1-1000 ppm at optimized operating temperature of 265 °C. The results showed that sensitivity (Rair/Rgas per ppm) goes on increasing with decreasing concentration of test gas, giving concentration dependent changes. Special studies carried out at low concentration levels (0.1-1 and 1-10 ppm) of H2, give high sensitivity (200 × 10-3/ppm) for lowest concentration (0.1-1 ppm) of H2. The selectivity for H 2 against relative humidity (RH), CO2, CO and LPG gases is also good. The sensor, at operating temperature of 200 °C, is showing nearly zero response to 300 ppm of H2, and offering response to acetone vapour of 11 ppm. Selectivity for acetone against RH% and CO2 was also studied. These sensors can be used as H2 sensor at an operating temperature of 265 °C, and as an acetone sensor at the operating temperature of 200 °C. © 2010 Elsevier B.V. All rights reserved.

Loading CMET - Photonics And Advanced Materials Laboratory collaborators
Loading CMET - Photonics And Advanced Materials Laboratory collaborators