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.

Electrochemical Characterization of Si/Al Multilayer Thin Film Anode Materials for High Energy Lithium Secondary Batteries

Patil, Vaishali,Patil, Arun,Yoon, Seok-Jin,Choi, Ji-Won American Scientific Publishers 2018 Science of advanced materials Vol.10 No.4

<P>Nanostructured silicon is a promising material for high capacity anodes in lithium batteries, offering a specific capacity an order of magnitude beyond conventional graphite. But the large volume change of silicon during lithiation and delithiation and the resulting poor cyclability has prevented its commercial application. Herein, we report Si/Al multilayer thin film electrodes which are deposited on a Ni substrate by alternate sputtering of Si and Al at room temperature. Si/Al multilayer thin films are prepared using an RF magnetron sputtering method, and their potential use as anode materials for rechargeable lithium-ion batteries is investigated. The insertion of the Al layer into the Si layer improves the cycling performance. Si/Al multilayer thin films show an amorphous structure. The electrochemical characteristics of Si/Al multilayer film electrode can be controlled by the thickness, and number of stacked Si layers. Our prepared multilayer structures provided a promising research platform that may eventually lead to an optimized anode structure for advanced rechargeable lithium secondary batteries.</P>

Improved electrochemical performance of activated carbon/polyaniline composite electrode

Patil, D.S.,Pawar, S.A.,Devan, R.S.,Ron Ma, Y.,Ri Bae, W.,Hyeok Kim, J.,Patil, P.S. North-Holland 2014 Materials Letters Vol.117 No.-

The composite thin films of activated carbon/polyaniline (AC/PANI) have been deposited on stainless steel substrates by a facile dip coating technique. Surface morphology of the films is examined by field emission scanning electron microscopy, which revealed aggregated nanofiber like structure for PANI and well distributed nanofibers with porous structure for AC/PANI films. The highest specific capacitance of 534Fg<SUP>-1</SUP> at 5mVs<SUP>-1</SUP> and energy density of 78.49Whkg<SUP>-1</SUP> at 1mAcm<SUP>-2</SUP> is observed for the AC/PANI electrode, indicating positive synergistic effect of AC and PANI.

Structural and electrochemical properties of Nichrome anode thin films for lithium battery

Patil, Arun,Patil, Vaishali,Choi, Ji-Won,Kim, Hyun-Jai,Cho, Bong-Hee,Yoon, Seok-Jin Springer-Verlag 2009 Journal of electroceramics Vol.23 No.2

Investigations on silver/polyaniline electrodes for electrochemical supercapacitors

Patil, Dipali S.,Shaikh, J. S.,Pawar, S. A.,Devan, R. S.,Ma, Y. R.,Moholkar, A. V.,Kim, J. H.,Kalubarme, R. S.,Park, C. J.,Patil, P. S. The Royal Society of Chemistry 2012 Physical chemistry chemical physics Vol.14 No.34

<P>Polyaniline (PANI) and silver doped polyaniline (Ag/PANI) thin films were deposited on stainless steel substrates by a dip coating technique. To study the effect of doping concentration of Ag on the specific capacitance of PANI the concentration of Ag was varied from 0.3 to 1.2 weight percent. Fourier transform-infrared and Fourier transform-Raman spectroscopy, and energy dispersion X-ray techniques were used for the phase identification and determination of the doping content in the PANI films, respectively. The surface morphology of the films was examined by Field Emission Scanning Electron Microscopy, which revealed a nanofiber like structure for PANI and nanofibers with bright spots of Ag particles for the Ag/PANI films. There was decrease in the room temperature electrical resistivity of the Ag/PANI films of the order of 10<SUP>2</SUP> with increasing Ag concentration. The supercapacitive behavior of the electrodes was tested in a three electrode system using 1.0 M H<SUB>2</SUB>SO<SUB>4</SUB> electrolyte. The specific capacitance increased from 285 F g<SUP>−1</SUP> (for PANI) to 512 F g<SUP>−1</SUP> for Ag/PANI at 0.9 weight percent doping of Ag, owing to the synergic effect of PANI and silver nanoparticles. This work demonstrates a simple strategy of improving the specific capacitance of polymer electrodes and may also be easily adopted for other dopants.</P> <P>Graphic Abstract</P><P>The presence of Ag nanoparticles on PANI nanofibers provides a least resistance path to electron transportation. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cp41757j'> </P>

A simple, room temperature, solid-state synthesis route for metal oxide nanostructures

Patil, Supriya A.,Shinde, Dipak V.,Ahn, Do Young,Patil, Dilip V.,Tehare, Kailas K.,Jadhav, Vijaykumar V.,Lee, Joong K.,Mane, Rajaram S.,Shrestha, Nabeen K.,Han, Sung-Hwan The Royal Society of Chemistry 2014 Journal of Materials Chemistry A Vol.2 No.33

<P>In this work, we demonstrate an extremely simple but highly effective strategy for the synthesis of various functional metal oxides (MOs) such as ZnO, In2O3, Bi2O3, and SnO2nanoparticles with various distinct shapes at room temperature<I>via</I>a solid-state reaction method. The method involves only mixing and stirring of the corresponding metal salt and NaOH together in the solid phase, which yields highly crystalline metal oxides within 5-10 min of reaction time. The obtained paste can be directly doctor-bladed onto a variety of substrates for photoelectrochemical applications. The crystal structure and surface composition of the MOs are obtained by X-ray diffraction patterns, energy dispersive analysis and X-ray photoelectron spectroscopy, respectively. The surface morphology is confirmed from the scanning electron microscopy surface photo-images. The surface area and pore size distribution are studied by the N2adsorption method. As a proof-of-concept demonstration for the application, ZnO nanoplate structures are envisaged in DSSCs as photoanodes, which enables us to obtain excellent photovoltaic properties with a power conversion efficiency of 5%. The proposed method does not require a sophisticated instrumental setup or harsh conditions, and the method is easily scalable. Hence, it can be applied for the cost-effective and large-scale production of MO nanoparticles with high crystallinity.</P>

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>

Morphologically controlled electrodeposition of fern shaped Bi₂Te₃ thin films for photoelectrochemical performance

Patil, P.B.,Mali, S.S.,Kondalkar, V.V.,Mane, R.M.,Patil, P.S.,Hong, C.K.,Bhosale, P.N. Elsevier Sequoia 2015 Journal of Electroanalytical Chemistry Vol.758 No.-

Bismuth telluride (Bi<SUB>2</SUB>Te<SUB>3</SUB>) thin films have been proved to be important materials for thermoelectric application. Rapid development of photovoltaic materials has raised new hopes due to directly converting sun light to electricity. We report here a simple electrochemical synthesis route for the preparation of well-defined Bi<SUB>2</SUB>Te<SUB>3</SUB> nanostructures for photoelectrochemical solar cell application. Classification of crystal structure, surface morphology and elemental composition of resulting deposits were methodically characterized by X-ray diffraction (XRD) pattern, Raman spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and its photoelectrochemical performance (PEC). The potential range and electrochemical reactions relevant to the growth of Bi<SUB>2</SUB>Te<SUB>3</SUB> thin films were studied by cyclic voltammetry (CV). Furthermore, the influence of deposition variables such as applied deposition potential and effect of different surfactants (cationic, anionic and non-ionic) on morphology, crystal orientation associated with the film growth and photoelectrochemical performance were investigated systematically. The photoelectrochemical conversion efficiency recorded for Bi<SUB>2</SUB>Te<SUB>3</SUB> is 0.083%.

[<b>ARTICLE WITHDRAWN</b>] Solid Electrolytes for Rechargeable Thin Film Lithium Batteries: A Review

Patil, Arun,Patil, Vaishali,Choi, Ji-Won,Kim, Jin-Sang,Yoon, Seok-Jin American Scientific Publishers 2017 Journal of Nanoscience and Nanotechnology Vol.17 No.1

<P>This reviews the history and the present status of the research and development of solid electrolyte in the lithium battery, and presents an outlook of the future research and development activities. The paper also introduces the improvement of lithium polymer secondary batteries using solid polymer electrolyte (SPE) such as poly(ethylene oxide) (PEO), poly(acrylonitrile) (PAN), poly(methyl methacrylate) (PMMA) with the performance and the applications of its present commercial products. We have tried to focus on the study of these advanced solid inorganic and polymer electrolytes by evaluating their use in rechargeable lithium batteries. Important factors for the solid electrolyte such as effect of preparative parameters, characterization techniques, parameters for the battery performance, importance of ionic conductivity has been explained. This article is the story of the development of solid electrolyte and it describes how the difficulties were surmounted. This review focuses first on the present status of lithium battery technology, then on its near future development and finally it examines important new directions aimed at achieving quantum jumps in energy and power content.</P>