Influence of reduced graphene oxide-TiO₂ composite nanofibers in organic indoline DN350 based dye sensitized solar cells

Patil, Jyoti V.,Mali, Sawanta S.,Shaikh, Jasmin S.,Patil, Akhilesh P.,Patil, Pramod S.,Hong, Chang Kook Elsevier 2019 Synthetic metals Vol.256 No.-

<P><B>Abstract</B></P> <P>In this study, the highly efficient organic indoline DN350 based dye sensitized solar cells (DSSCs) have been fabricated using reduced graphene oxide (rGO)-TiO<SUB>2</SUB> composite nanofibers (NFs) and tested its photovoltaic properties. The influence of the rGO on the morphology, structural properties of the TiO<SUB>2</SUB> NFs have been characterized by various techniques. Our photovoltaic results revealed that the modified rGO-TiO<SUB>2</SUB> composite NFs exhibited higher power conversion efficiency (PCE) in comparison with the pristine-TiO<SUB>2</SUB> NFs. The electrochemical analysis indicated that the GO content provides more active sites results in higher dye adsorption which consequently improves the DSSCs performance. Our optimized sample containing 4 mg-rGO-TiO<SUB>2</SUB> NFs exhibited the best performance with 4.43% PCE, which is higher than the pristine-TiO<SUB>2</SUB> NFs (3.83%). Overall, this study presents the rGO-TiO<SUB>2</SUB> composite NFs as a novel strategy for enhancing the efficiency of the organic indoline DN350 based DSSCs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Electrospun reduced graphene oxide (rGO)-TiO<SUB>2</SUB> composite nanofibers. </LI> <LI> rGO-TiO<SUB>2</SUB> composite nanofibers for organic indoline DN350 DSSCs. </LI> <LI> The 4.42% power conversion efficiency achieved for DSSC. </LI> </UL> </P>

Spherical crystallization of ezetimibe for improvement in physicochemical and micromeritic properties

Ashwini Patil,Yogesh Pore,Yogesh Gavhane,Shitalkumar Patil,Sachinkumar Patil 한국약제학회 2014 Journal of Pharmaceutical Investigation Vol.44 No.3

Spherical agglomerates of ezetimibe (EZT)were prepared with hydrophilic polymers; polyvinyl pyrrolidoneK30 (PVP) and/or poloxamer 188 (poloxamer) atdrug to polymer ratios of 1:1 (w/w) by spherical crystallizationtechnique, in order to improve its physicochemicaland micromeritic properties. Three different bridging liquids;chloroform, dichloromethane and/or ethyl acetatealong with good solvent acetone and poor solvent waterwere used to form six batches of agglomerates. Initialcharacterization of all batches in terms of micromeritic andphysicochemical properties resulted in optimization of (A3,EZT:PVP:ethyl acetate) and (B3, EZT:poloxamer:ethylacetate) batches and hence further investigated for drug–polymer interaction, crystallinity and morphology usingFTIR, XRPD, DSC and SEM techniques. The resultsindicated presence of hydrogen bonding, crystallinity andspherical shape in agglomerates. Therefore, the optimizedagglomerates (B3) were directly compressed into tablet. Unfortunately, drug release from the tablet was not satisfactory,suggesting a need of disintegrant from dissolutionpoint of view. Therefore, these agglomerates were recompressedincorporating certain excipients and evaluated asper pharmacopoeia. The dissolution rate of prepared tabletwas similar to that of marketed tablet (p[0.05). It couldbe concluded that spherical crystallization could be one ofthe effective and alternative approaches for improvedperformance of EZT and its tablet formulation.

Fabrication of nanostructured ZnO thin films based NO₂ gas sensor via SILAR technique

Patil, Vithoba L.,Vanalakar, Sharadrao A.,Patil, Pramod S.,Kim, Jin H. Elsevier Sequoia 2017 Sensors and actuators. B Chemical Vol.239 No.-

<P><B>Abstract</B></P> <P>Zinc oxide (ZnO) thin films have been widely used as an effective gas sensor element. In the present study, nanostructured thin films of ZnO were prepared by using the simplistic and economical successive ion layer adsorption and reaction (SILAR) technique. The effects of SILAR cycles on the structural, optical, surface morphological and electrical properties of nanostructured ZnO thin films were investigated. Characterization techniques such as XRD, UV-vis, PL, FESEM, and Hall measurement were utilized to study the physical and chemical properties of the synthesized films. XRD confirms the formation of hexagonal phase structural ZnO thin films. FE-SEM analysis reveals the formation of well-dispersed ZnO nanoparticles having sizes of ∼18–40nm. The SILAR cycles play a key role in the synthesis of nanostructured ZnO thin films and it is found that, with increasing SILAR cycles, the grain size continues increasing. Optical studies confirm the presence of oxygen vacancies in synthesized ZnO thin films. Finally, the ZnO thin films were exposed to NO<SUB>2</SUB> gas with a concentration of 100ppb–200ppm and the resulting resistance transient was recorded. The nanostructured ZnO thin films synthesized at 30 SILAR cycles displays an enhancement of gas sensing performance and exhibit significantly higher responses (∼5%per ppm). Moreover, our ZnO thin-film-based gas sensor is sensitive to very low concentrations of dangerous NO<SUB>2</SUB> (100ppb). The sensitive gas sensor used to trace level NO<SUB>2</SUB> detection, synthesized via simple SILAR route proves the novelty of our work. The present report provides a new direction in fabricating nanostructured ZnO thin films for low-cost and efficient gas sensing applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Preparation of nanostructured ZnO by using the simplistic SILAR technique. </LI> <LI> Formation of well-dispersed ZnO nanoparticles having sizes of ∼18–40nm. </LI> <LI> The ZnO thin films were exposed to NO<SUB>2</SUB> gas with a concentration of 100ppb–200ppm. </LI> <LI> Our ZnO based gas sensor is sensitive to very low concentrations of dangerous NO<SUB>2</SUB> (100ppb). </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Determination of Heparin Using Norfloxacin-cerium Complex as a Fluorescence Probe by Spectrofluorimetry

Patil, Shailaja R.,Mote, Umesh S.,Patil, Shivajirao R.,Kolekar, Govind B. Korean Chemical Society 2009 Bulletin of the Korean Chemical Society Vol.30 No.12

A simple, rapid, practical and sensitive spectofluorimetric method was developed for the determination of trace amount of heparin (Hep). Under the Optimum conditions, we studied the interaction between NFLX-Ce$^{3+}$-Hep complex by using absorption and fluorescence spectra. It was observed that Hep remarkably enhance the fluorescence intensity of the NFLX-Ce$^{3+}$ complex at ${\lambda}$= 356 nm in the buffer solution of pH = 7.60 and the enhancement effect is shown to relate with the concentration of Hep. The linear range and detection limit for the determination of Hep was obtained. By the Rosenthal graphic method, the association constant (K) and binding numbers (N) of Hep with probe were investigated. This method is relatively free of interference from coexisting substances and successfully applied for the determination of heparin in heparin sodium injection samples. A suitable mechanism of fluorescence enhancement between NFLX-Ce$^{3+}$ and the NFLX-Ce$^{3+}$-Hep systems were proposed and discussed.

Gas sensing properties of 3D mesoporous nanostructured ZnO thin films

Patil, V. L.,Kumbhar, S. S.,Vanalakar, S. A.,Tarwal, N. L.,Mali, S. S.,Kim, J. H.,Patil, P. S. The Royal Society of Chemistry 2018 New journal of chemistry Vol.42 No.16

<P>Advancing the properties of selective and sensitive metal oxide based gas sensors is a challenging research topic for the detection of toxic, and pollutant gases. In the present research, we successfully deposited a three dimensional (3D) mesoporous ZnO nanostructure on a glass substrate by using a hydrothermal method, and tested the material for its gas sensing performance. These 3D mesoporous ZnO nanostructures were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and photoluminescence techniques. Gas sensing performance analysis was carried out for nitrogen dioxide (NO2) gas at different temperatures and concentrations. The 3D mesoporous ZnO nanostructure revealed excellent gas sensing performance for NO2 gas because of its large surface area. The larger surface area led to an increase in the gas sensitivity. In addition, the sensor based on the 3D mesoporous ZnO nanostructure could be used at a low operating temperature of 150 °C. This work suggests that the 3D mesoporous ZnO nanostructure is a versatile material for NO2 gas sensing applications.</P>

Polyaniline based electrodes for electrochemical supercapacitor: Synergistic effect of silver, activated carbon and polyaniline

Patil, D.S.,Pawar, S.A.,Devan, R.S.,Mali, S.S.,Gang, M.G.,Ma, Y.R.,Hong, C.K.,Kim, J.H.,Patil, P.S. Elsevier Sequoia 2014 Journal of electroanalytical chemistry Vol.724 No.-

The composite thin films of Silver-activated carbon/polyaniline (Ag-AC/PANI) have been deposited on stainless steel substrates by a facile dip coating technique. The formation of Ag-AC/PANI electrode is analyzed by Fourier transform infrared, Fourier transform-Raman and X-ray photoelectron spectroscopy techniques. Field Emission Scanning Electron Microscopy revealed the presence of Ag nanoparticles on the porous spongy background of PANI. The highest specific capacitance of 567Fg<SUP>-1</SUP>at 5mVs<SUP>-1</SUP> and energy density of 86.30Whkg<SUP>-1</SUP> at 1mAcm<SUP>-2</SUP> is observed for the Ag-AC/PANI indicating positive synergistic effect of silver, activated carbon and PANI. In which silver nanoparticles help in improving the electronic conductivity and activated carbon enhances the electrochemical stability of the PANI electrodes.

An approach towards TiO2 chrysanthemum flowers with tunable properties: influence of reaction time in hydrothermal process

Patil, P. B.,Mali, S. S.,Kondalkar, V. V.,Khot, K. V.,Mane, R. M.,Hong, C. K.,Patil, P. S.,Kim, J. H.,Bhosale, P. N. Springer Science + Business Media 2015 Journal of materials science Materials in electron Vol.26 No.8

LiCoO2 thin film cathodes grown by sol-gel method

Patil, Vaishali,Patil, Arun,Choi, Ji-Won,Lee, Yoon-Pyo,Yoon, Young Soo,Kim, Hyun-Jai,Yoon, Seok-Jin Springer-Verlag 2009 JOURNAL OF ELECTROCERAMICS Vol.23 No.2

Graphene-wrapped Ag 3 PO 4 /LaCO 3 OH heterostructures for water purification under visible light

Patil, Santosh S.,Mali, Mukund G.,Roy, Animesh,Tamboli, Mohaseen S.,Deonikar, Virendrakumar G.,Patil, Deepak R.,Kulkarni, Milind V.,Al-Deyab, Salem S.,Yoon, Sam S.,Kolekar, Sanjay S.,Kale, Bharat B. Elsevier 2016 Journal of energy chemistry Vol.25 No.5

<P>We demonstrated a unique synthesis approach of graphene (GR)-wrapped Ag3PO4/LaCO3OH (APO/LCO) heterostructures by an in-situ wet chemical method. FESEM analysis reveals the formation of rhombic dodecahedrons of APO decorated with LCO and later wrapped with GR flakes. Optical studies shows two absorption edges corresponding to the band gap energies of APO (2.41 eV) and LCO (4.1 eV). Considering the absorption edge of the heterostructures in the visible region, the photocatalytic activities of photocatalysts containing different APO/LCO mass ratios were evaluated by the degradation of MB. GR-decorated composite with 20% LCO (APO/LCO20/GR) exhibited the highest photocatalytic activity for MB degradation, with a rate constant, k of 0.541 min(-1). The photocatalytic activity of APO/LCO20/GR more greatly enhanced than those of the individual constituents (APO, LCO, APO/LCO20). The enhanced photocatalytic activity of the heterostructure can be attributed to the co-catalytic effect of LCO as well as intriguing physicochemical properties of GR. To understand the enhanced photocatalytic activity of the heterostructures the photocatalytic reaction mechanism is proposed in detail. The recyclability of the APO/LCO/GR composite photocatalyst is further evaluated by reusing the catalyst in replicate photocatalytic experiments which shows consistent photocatalytic activity thereby confirms the stability and reusability of heterostructure photocatalyst. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.</P>

Facile Preparation and Enhanced Capacitance of the Ag-PEDOT:PSS/Polyaniline Nanofiber Network for Supercapacitors

Patil, D.S.,Pawar, S.A.,Kim, J.H.,Patil, P.S.,Shin, J.C. Pergamon Press 2016 Electrochimica Acta Vol. No.

This paper reports the synthesis of a silver - Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)/Polyaniline(Ag-PEDOT:PSS/PANI)hybrid nanostructure using a simple dip coating technique followed by potentiodynamic electrodeposition to achieve an electrochemical supercapacitor with excellent electrochemical performance. In this sandwich type structure, the Ag nanostructure-blended PEDOT: PSS acts as a current collector, where electrons can be transferred easily through this network to the PANI nanofibers and vice versa. The AgNW-PEDOT:PSS/PANI showed a specific capacitance of 643 Fg<SUP>-1</SUP> at 10 mVs<SUP>-1</SUP> and an energy density of 86.19 Whkg<SUP>-1</SUP> at 0.1mA, indicating the positive synergistic effect of silver nanowires (AgNW), PEDOT:PSS and PANI. The Ag nanostructure incorporated PEDOT:PSS helps to improve the electronic conductivity and the electrochemical stability of the PANI electrodes. Promising electrochemical properties achieved from the measurement of symmetric device demonstrate the ideal capacitive behavior of our prepared electrodes.