Shivaji University

About: Shivaji University is a education organization based out in Kolhāpur, Maharashtra, India. It is known for research contribution in the topics: Thin film & Scanning electron microscope. The organization has 3078 authors who have published 5295 publications receiving 115397 citations.

N-methyl isatin nanoparticles as a novel probe for selective detection of Cd2+ ion in aqueous medium based on chelation enhanced fluorescence and application to environmental sample

Abstract: The fluorescent N -methyl isatin nanoparticles ( N -MINPs) were prepared by a simple reprecipitation method. The prepared N -MINPs examined by dynamic light scattering (DLS) show narrower particle size distribution having an average particle size of 112 nm. The scanning electron microphotograph shows distinct spherical shaped morphology of nanoparticles. The UV-absorption and fluorescence spectra of aqueous suspension of N -MINPs are blue shifted from the corresponding spectra of N -methyl isatin solution in acetone. The blue shift indicates the H-aggregates and Aggregation Induced Enhanced Emission (AIEE) from nanoparticles. The nanoparticles have high stability without any stabilizer and functional keto moiety recognized Cd 2+ ions selectively by enhancing the fluorescence preference to Ni 2+ , Cu 2+ , Hg 2+ , Sn 2+ , Pb 2+ , Ca 2+ , Zn 2+ , Na + , K + , Co 2+ and Mg 2+ ions which actually seem to quench the fluorescence of nanoparticles. The studies on fluorescence lifetime of N -MINPs and its fluorescence titration with and without Cd 2+ helped to propose a suitable mechanism of fluorescence enhancement of nanoparticles by Cd 2+ and their binding ability during complexation. The fluorescence enhancement effect of N -MINPs induced by Cd 2+ is further used to develop analytical method for detection of Cd 2+ from aqueous medium in environmental samples based on chelation enhanced fluorescence approach.

Influence of Mn incorporation on the supercapacitive properties of hybrid CuO/Cu(OH)2 electrodes

Abstract: Here, we are presenting the effect of Mn doping on the supercapacitive properties of CuO/Cu(OH)2 hybrid electrodes. Briefly, Mn doped CuO/Cu(OH)2 (Mn:CuO/Cu(OH)2) thin films have been synthesized by a successive ionic layer adsorption and reaction (SILAR) method which are further characterized by different physiochemical techniques. Our results revealed the formation of hybrid CuO/Cu(OH)2 thin films with significant morphological deviation through Mn doping. Moreover, considerable positive effect of Mn doping on the electrochemical properties of hybrid CuO/Cu(OH)2 electrodes have been witnessed. Later, the results suggest that at 3% Mn doping in CuO/Cu(OH)2 electrodes with nanoflower-like nanostructures exhibits the highest specific capacitance. The maximum specific capacitance achieved for a 3% Mn:CuO/Cu(OH)2 hybrid electrode is 600 F g−1 at 5 mV s−1 in 1 M Na2SO4 electrolyte. Additionally, a Ragone plot confirms the potential of the Mn:CuO/Cu(OH)2 hybrid electrode for electrical energy storage applications.

Improved response of CdO nanorods towards liquefied petroleum gas (LPG): Effect of Pd sensitization

Abstract: Liquefied petroleum gas (LPG) sensors have been fabricated using cadmium oxide nanorods obtained by a chemical bath deposition (CBD) method. The response of the CdO nanorod network to LPG was improved significantly after palladium (Pd) sensitization by a dip and dry method. Before exposing for the sensing application, these films were characterized for its structural, morphological and compositional analysis using XRD, FESEM, EDX, etc. The LPG sensing properties of the unsensitized and Pd-sensitized CdO were investigated at different operating temperatures and LPG concentrations. The unsensitized CdO exhibited the maximum response of 14% at 698 K upon exposure to 0.1 vol% of LPG that was improved up to 35% at an optimum operating temperature of 548 K after the Pd sensitization. The Pd-sensitized CdO film showed more selectivity towards LPG as compared to CO2 (i.e. 3.18% for Pd-sensitized CdO and 2.8% for unsensitized CdO). Additionally, the stability of the films has been studied.

Infrared absorption spectroscopic study of Nd3+ substituted Zn-Mg ferrites

Abstract: Compositions of polycrystalline ZnxMg1−xFe2−yNdyO4 (x = 0.00, 0.20, 0.40, 0.60, 0.80 and 1.00;y = 0.00, 0.05 and 0.10) ferrites were prepared by standard ceramic method and characterized by X-ray diffraction, scanning electron microscopy and infrared absorption spectroscopy. Far infrared absorption spectra show two significant absorption bands, first at about 600 cm−1 and second at about 425 cm−−1, which were respectively attributed to tetrahedral (A) and octahedral (B) sites of the spinel. The positions of bands are found to be composition dependent. The force constants,KT andKO, were calculated and plotted against zinc concentration. Compositional dependence of force constants is explained on the basis of cation-oxygen bond distances of respective sites and cation distribution.