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.

Confinement of Ag₃PO₄ nanoparticles supported by surface plasmon resonance of Ag in glass: Efficient nanoscale photocatalyst for solar H₂ production from waste H₂S

Patil, S.S.,Patil, D.R.,Apte, S.K.,Kulkarni, M.V.,Ambekar, J.D.,Park, C.J.,Gosavi, S.W.,Kolekar, S.S.,Kale, B.B. Elsevier 2016 Applied Catalysis B Vol.190 No.-

<P>Ag3PO4 is a good photocatalyst but ubiquitously known for its photocorrosion problem during photocatalytic reaction. Therefore, stabilization of Ag3PO4 with retaining its fundamental properties has immense importance. With this motivation, we designed Ag3PO4 glass nanocomposite to resolve the problem of photocorrosion. Moreover, the effect of size quantization on photocatalytic activity has also been demonstrated by growing the cubic Ag3PO4 nanoparticles with size in the range of 3-9 nm in glass matrix via melt and quenching method. The band gap of Ag3PO4 has been tuned (2.56-2.25 eV) in glass matrix with respect to size. Considering the size tunable band gap of Ag3PO4 glass nanocomposite within visible region, it is demonstrated as a photocatalyst for hydrogen (H-2) production from copious hazardous waste H2S. The utmost H-2 production i.e. 3920.4 mu mol h(-1) g(-1) is obtained using 1 gm of Ag3PO4 glass nanocomposite powder. The apparent quantum yield for H-2 production is calculated to be 5.51% for Ag3PO4 glass nanocomposite. Interestingly, presence of plasmonic Ag was also observed in Ag3PO4 glass nanocomposite which contributes for H-2 production through enhanced light absorption, efficient charge separation and improved stability. Recycling study of sample reveals stable H-2 production efficiency and good stability of the photocatalyst. Surprisingly, catalyst can be reused many times and recovery of catalyst is possible just rinsing with distilled water. All these results demonstrate directly the feasibility of designing a new generation photocatalysts. (C) 2016 Published by Elsevier B.V.</P>

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>

Tailor-made dicationic ionic liquid as a fluorescent sensor for detection of hydroquinone and catechol

Patil, Sandip K.,Patil, Suryakant A.,Vadiyar, Madagonda M.,Awale, Deepak V.,Sartape, Ashish S.,Walekar, Laxman S.,Kolekar, Govind B.,Ghorpade, Uma V.,Kim, Jin H.,Kolekar, Sanjay S. Elsevier 2017 Journal of molecular liquids Vol.244 No.-

<P>We are exploring a geminal dicationic ionic liquid (DCIL), 1,1'-(propane-1,3-diyl)bis(4-aminopyridin-1-ium) dihydroxide, [C-3(Amp)(2)][OH](2) as a fluorescent probe for detection of dihydroxybenzenes viz. hydroquinone (HQ) and catechol (CC). Simple and sensitive spectrofluorometric method is described which accomplished with efficient quenching of fluorescence of aqueous DCIL by dihydroxybenzenes. The sensor offers good linear detection range of 1-400 mu M and 1-1000 mu M with detection limits of 0.31 mu M and 0.40 mu M for HQ and CC, respectively. Under alkaline conditions HQ/CC oxidizes to corresponding benzoquinones which interact with DCIL and consequently quenching of fluorescence is occurred. This essential alkaline condition is in situ provided by purposefully tuned DCIL to having basic nature. The plausible quenching mechanism that involves photo-induced charge transfer pathway is evidently discussed. The proposed method is competent over a broad detection range. Selectivity of method is demonstrated by scrutinizing intervention of various interfering species. Recoveries from water sample analysis emphasize the possible use of DCIL probe in the detection of HQ and CC from water sources. The proposed method certainly confers a new approach in sensing techniques for dihydroxybenzenes. (C) 2017 Published by Elsevier B.V.</P>

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>

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>

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.

Green approach for hierarchical nanostructured Ag-ZnO and their photocatalytic performance under sunlight

Patil, S.S.,Mali, M.G.,Tamboli, M.S.,Patil, D.R.,Kulkarni, M.V.,Yoon, H.,Kim, H.,Al-Deyab, S.S.,Yoon, S.S.,Kolekar, S.S.,Kale, B.B. Elsevier Science Publishers 2016 CATALYSIS TODAY - Vol.260 No.-

<P>In this study, the synthesis of silver-zinc oxide (Ag-ZnO) nanostructures with a plant-extract-mediated hydrothermal method was investigated. The eco-friendly plant extract Azadirachta indica (Neem) was used as a reducing agent. The X-ray diffraction patterns showed the formation of face-centered cubic (fcc) Ag nanoparticles (NPs) and a wurtzite ZnO structure. An optical study of these nanostructures revealed two absorption edges: one at 393 nm corresponding to ZnO and the other at approximately 440 nm corresponding to Ag. A morphology study showed that hierarchical ZnO nanostructures were decorated with 10-50-nm-diameter Ag NPs. The formation and growth mechanism were also examined. A photoelectrochemical study was performed to investigate the electronic interactions between the ZnO and Ag NPs in the photoanode upon exposure to light. The Ag NPs act as electron acceptors, inhibiting electron-hole recombination. The photocatalytic activity of the Ag-ZnO nanostructures was examined by observing the degradation of aqueous methylene blue (MB) dye under natural sunlight. The apparent rate constant determined for the photocatalytic degradation of MB by the Ag-ZnO nanostructures was 5.9668 x 10(-2) min(-1), which was faster than that of the untreated ZnO nanostructures (2.527 x 10(-2) mm(-1)). This plant-extract-mediated synthetic route could also be applied to the synthesis of other Ag-semiconductor oxide nanostructures. (C) 2015 Elsevier B.V. All rights reserved.</P>