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>

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>

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>

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>

Development of nanocoral-like Cd(SSe) thin films using an arrested precipitation technique and their application

Khot, Kishorkumar V.,Mali, Sawanta S.,Pawar, Nita B.,Kharade, Rohini R.,Mane, Rahul M.,Kondalkar, Vijay V.,Patil, Pallavi B.,Patil, Pramod S.,Hong, Chang K.,Kim, Jin H.,Heo, Jaeyeong,Bhosale, Popatrao The Royal Society of Chemistry 2014 New journal of chemistry Vol.38 No.12

<P>Nanocrystalline cadmium sulfoselenide thin films have been synthesized using a self-organized arrested precipitation technique with different deposition times using triethanolamine as a complexing agent. Optical, structural, morphological and photoelectrochemical solar cell properties were investigated as a function of deposition time. A UV-Vis-NIR absorption study suggested a direct allowed transition type and the band gap energy decreased from 2.01 to 1.86 eV with the increase in deposition time. X-ray diffraction studies revealed that the thin films are nanocrystalline by nature with a pure hexagonal crystal structure and a calculated crystallite size of 51–68 nm. Field emission scanning electron microscopy demonstrated that the surface morphology was altered from nanoflakes to assorted nanoflakes–nanospheres and finally to a nanocoral-like morphology. X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy showed that the composition of the Cd(SSe) thin films was of good stoichiometry. Electrical conductivity and thermoelectric power measurements confirmed that the deposited films were n-type semiconductors. From <I>J–V</I> measurements, a highest photo-conversion efficiency of 0.57% was achieved. The significant boost in the PEC performance might be due to the improved crystallinity along with lower values of the grain boundary resistance, dislocation density and the microstrain of the Cd(SSe) thin films.</P> <P>Graphic Abstract</P><P>First-time synthesis of nanoflakes to nanocoral-like Cd(SSe) thin films using a novel arrested precipitation technique with triethanolamine as complexing agent (<I>η</I> = 0.57%). <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c4nj01319k'> </P>

Improved Photoelectrochemical Cell Performance of Tin Oxide with Functionalized Multiwalled Carbon Nanotubes–Cadmium Selenide Sensitizer

Bhande, Sambhaji S.,Ambade, Rohan B.,Shinde, Dipak V.,Ambade, Swapnil B.,Patil, Supriya A.,Naushad, Mu.,Mane, Rajaram S.,Alothman, Z. A.,Lee, Soo-Hyoung,Han, Sung-Hwan American Chemical Society 2015 ACS APPLIED MATERIALS & INTERFACES Vol.7 No.45

<P>Here we report functionalized multiwalled carbon nanotubes (<I>f</I>-MWCNTs)–CdSe nanocrystals (NCs) as photosensitizer in photoelectrochemical cells, where <I>f</I>-MWCNTs were uniformly coated with CdSe NCs onto SnO<SUB>2</SUB> upright standing nanosheets by using a simple electrodeposition method. The resultant blended photoanodes demonstrate extraordinary electrochemical properties including higher Stern–Volmer constant, higher absorbance, and positive quenching, etc., caused by more accessibility of CdSe NCs compared with pristine SnO<SUB>2</SUB>–CdSe photoanode. Atomic and weight percent changes of carbon with <I>f</I>-MWCNTs blending concentrations were confirmed from the energy dispersive X-ray analysis. The morphology images show a uniform coverage of CdSe NCs over <I>f</I>-MWCNTs forming a core–shell type structure as a blend. Compared to pristine CdSe, photoanode with <I>f</I>-MWCNTs demonstrated a 257% increase in overall power conversion efficiency. Obtained results were corroborated by the electrochemical impedance analysis. Higher scattering, more accessibility, and hierarchical structure of SnO<SUB>2</SUB>-<I>f</I>-MWCNTs-blend–CdSe NCs photoanode is responsible for higher (a) electron mobility (6.89 × 10<SUP>–4</SUP> to 10.89 × 10<SUP>–4</SUP> cm<SUP>2</SUP> V<SUP>–1</SUP> S<SUP>1–</SUP>), (b) diffusion length (27 × 10<SUP>–6</SUP>), (c) average electron lifetime (32.2 ms), and transit time (1.15 ms).</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2015/aamick.2015.7.issue-45/acsami.5b05385/production/images/medium/am-2015-05385e_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/am5b05385'>ACS Electronic Supporting Info</A></P>

Role of Ceramic Coating on Electrical and Magnetic Properties of Iron Powder

N. B. Dhokey,S. Patil,S. Dhandare,V. S. Bandal 대한금속·재료학회 2014 ELECTRONIC MATERIALS LETTERS Vol.10 No.3

Soft magnetic composite is a promising second generation magnetic material. It is widely used in both DC and AC applications. In the present work, magnesium compound coated iron powder (M-SMC) was used to fabricate the toroid cores of size Ø 30 × Ø 20 × 10 mm by powder metallurgy route. All these toroid cores were cured at different temperatures ranging from 600°C to 1000°C for 30 min in argon atmosphere controlled furnace. The electrical and magnetic properties of toroid cores were analyzed by Impedance Analyzer and B-H Analyzer respectively. M-SMC core cured at 800°C showed improved electrical properties for operating frequency up to 12000 kHz whereas magnetic properties were limited to applied magnetic field of 800 A/m.

Nitrogen doped waste tea residue derived carbon dots for selective quantification of tetracycline in urine and pharmaceutical samples and yeast cell imaging application

Gunjal, Datta B.,Gurav, Yogesh M.,Gore, Anil H.,Naik, Vaibhav M.,Waghmare, Ravindra D.,Patil, Chandrashekhar S.,Sohn, Daewon,Anbhule, Prashant V.,Shejwal, Rajendra V.,Kolekar, Govind B. North-Holland 2019 Optical materials Vol.98 No.-

<P><B>Abstract</B></P> <P>In this work, waste tea residue, abundantly accessible, is utilized for synthesis of fluorescent carbon dots (CDs) by a simple, low cost and one step chemical oxidation method. The optical properties, surface functionality and particle size of CDs were ascertained by various techniques. The CDs exhibited excellent water solubility, optical properties, bioimaging ability etc. The fluorescence intensity of the CDs was diminished gradually with increasing concentrations of tetracycline drug owing to the inner filter effect (IFE) phenomenon. The developed fluorescent probe displayed a better linear range, excellent detection limit and interference free response to the tetracycline. This resulted in quantification of tetracycline in real sample which achieved almost 99% recoveries indicated excellent practical potential. Moreover, the CDs were used as fluorescent label for multicolour imaging of yeast cells which could open the doors for further research in biological fields.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Carbon Dots derived from waste tea residue by simple reflux method. </LI> <LI> Determination of Tetracycline by fluorescence quenching through inner filter mechanism. </LI> <LI> Simple, sensitive and interference free method. </LI> <LI> Carbon dots as a fluorescent label for multicolour cell imaging. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Schematic of synthesis of CDs and inner filter effect based detection of tetracycline.</P> <P>[DISPLAY OMISSION]</P>

Biodegradation and metabolic fate of levofloxacin via a freshwater green alga, <i>Scenedesmus obliquus</i> in synthetic saline wastewater

Xiong, Jiu-Qiang,Kurade, Mayur B.,Patil, Dilip V.,Jang, Min,Paeng, Ki-Jung,Jeon, Byong-Hun Elsevier 2017 Algal research Vol.25 No.-

<P><B>Abstract</B></P> <P>Levofloxacin (LEV), a fluoroquinolone antibiotic has been frequently observed in water resources imposing ecotoxicological effects on aquatic microbiota. The biodegradation and metabolic fate of LEV via a microalga, <I>Scenedesmus obliquus</I> in synthetic saline wastewater were investigated in this study. LEV removal (1mgL<SUP>−1</SUP>) by <I>S. obliquus</I> was relatively low in the synthetic wastewater without the addition of sodium chloride (NaCl); however, its removal increased significantly from 4.5 to 93.4% with increasing of its salinity from 0 to 171mM NaCl. Kinetic studies showed that the removal rate constant (k) increased from 0.005 to 0.289d<SUP>−1</SUP> and degradation half-life decreased from 272 to 5d in the presence of NaCl (0–856mM). The removal mechanism analysis showed that the major mechanism of NaCl mediated enhancement of LEV removal was the bioaccumulation and subsequent intracellular biodegradation of LEV in microalgal cells. Six metabolites were identified via gas chromatography–mass spectrometry analysis after biodegradation of LEV. A metabolic pathway was postulated with regard to various cellular biocatalytic reactions in <I>S. obliquus</I>, including decarboxylation, demethylation, dehydroxylation, side chain breakdown, and ring cleavage.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>Scenedesmus obliquus</I> was tolerant to levofloxacin, and could withstand its high doses. </LI> <LI> 96h EC<SUB>50</SUB> of levofloxacin for <I>C. vulgaris</I> was 65mgL<SUP>−1</SUP>. </LI> <LI> Addition of NaCl stimulated the biodegradation of levofloxacin up to 93.4%. </LI> <LI> <I>Scenedesmus obliquus</I> can biotransform levofloxacin in simple metabolic byproducts. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

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