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.
Bhirud A.P.,CMET - Photonics And Advanced Materials Laboratory |
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.
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.