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>

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%.

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>

Structural and electrical properties of NASICON type solid electrolyte nanoscaled glass-ceramic powder by mechanical milling for thin film batteries.

Patil, Vaishali,Patil, Arun,Yoon, Seok-Jin,Choi, Ji-Won American Scientific Publishers 2013 Journal of Nanoscience and Nanotechnology Vol.13 No.5

<P>During last two decades, lithium-based glasses have been studied extensively as electrolytes for solid-state secondary batteries. For practical use, solid electrolyte must have high ionic conductivity as well as chemical, thermal and electrochemical stability. Recent progresses have focused on glass electrolytes due to advantages over crystalline solid. Glass electrolytes are generally classified into two types oxide glass and sulfide glass. Oxide glasses do not react with electrode materials and this chemical inertness is advantageous for cycle performances of battery. In this study, major effort has been focused on the improvement of the ion conductivity of nanosized LiAlTi(PO4)3 oxide electrolyte prepared by mechanical milling (MM) method. After heating at 1000 degrees C the material shows good crystallinity and ionic conductivity with low electronic conductivity. In LiTi2(PO4)3, Ti4+ ions are partially substituted by Al3+ ions by heat-treatment of Li20-Al2O3-TiO2-P2O5 glasses at 1000 degrees C for 10 h. The conductivity of this material is 1.09 x 10(-3) S/cm at room temp. The glass-ceramics show fast ion conduction and low E(a) value. It is suggested that high conductivity, easy fabrication and low cost make this glass-ceramics promising to be used as inorganic solid electrolyte for all-solid-state Li rechargeable batteries.</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>

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.

Silver incorporated PEDOT: PSS for enhanced electrochemical performance

Patil, D.S.,Pawar, S.A.,Hwang, J.,Kim, J.H.,Patil, P.S.,Shin, J.C. Korean Society of Industrial and Engineering Chemi 2016 Journal of industrial and engineering chemistry Vol.42 No.-

A simple strategy is proposed for the development of silver (Ag) incorporated Poly (3,4-ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) electrodes for electrochemical supercapacitors. To examine the effects of the Ag on the specific capacitance and energy density of PEDOT:PSS, its concentration was varied from 0.3 to 1.5wt.% Ag. Surface morphology of the films is examined by field emission scanning electron microscopy, which revealed the smooth surface for PEDOT:PSS and existence of small Ag bright spots onto the smooth surface of PEDOT:PSS for the Ag-PEDOT:PSS. The electrochemical activity of PEDOT:PSS was enhanced after its interaction with Ag. An electrode with 0.9wt.% Ag in PEDOT:PSS showed superior specific capacitance (172Fg<SUP>-1</SUP>) and energy density (36.11WhKg<SUP>-1</SUP>) due to the synergistic effect of both Ag and PEDOT:PSS. These results were extensively examined using different characterization tools. This study will provide a new avenue for designing low cost and excellent electrochemical performance electrode based on Ag-PEDOT:PSS for better supercapacitors.

Antispermatogenic and antiandrogenic activities of various extracts of Melia azedarach Linn. seeds in albino rats

Patil, Sharanabasappa A.,Malashetty, Vijaykumar B.,Patil, Saraswati B. Kyung Hee Oriental Medicine Research Center 2003 Oriental pharmacy and experimental medicine Vol.3 No.3

Petroleum ether, chloroform and ethanol extracts of the seeds of Melia azedarach Linn. administered orally to male rats at the dose level of 25 mg/100 g body weight for 48 days showed antispermatogenic activity, as the number of spermatocytes, spermatids and spermatozoa was decreased. The total cholesterol content was increased while protein and glycogen contents were decreased. The acid phosphatase content was also decreased while that of alkaline phosphatase increased. At the same time the weight of caput and cauda epididymis, prostate gland, seminal vesicle and Levator Ani muscle was decreased indicating its antiandrogenic property. Of the three extracts, the petroleum ether extract was more potent in its antispermatogenic and antiandrogenic activities and did not produce any sings of toxicity upto a dose of 25 mg/100 g body weight oral administration. After subjecting it to preliminary phytochemical screening the petroleum ether extract showed positive tests for steroids and saponins.