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>

Acetoclastic methanogenesis led by <i>Methanosarcina</i> in anaerobic co-digestion of fats, oil and grease for enhanced production of methane

Kurade, Mayur B.,Saha, Shouvik,Salama, El-Sayed,Patil, Swapnil M.,Govindwar, Sanjay P.,Jeon, Byong-Hun Elsevier Applied Science 2019 Bioresource Technology Vol. No.

<P><B>Abstract</B></P> <P>Fats, oil and grease (FOG) are energy-dense wastes that substantially increase biomethane recovery. Shifts in the microbial community during anaerobic co-digestion of FOG was assessed to understand relationships between substrate digestion and microbial adaptations. Excessive addition of FOG inhibited the methanogenic activity during initial phase; however, it enhanced the ultimate methane production by 217% compared to the control. The dominance of Proteobacteria was decreased with a simultaneous increase in Firmicutes, Bacteriodetes, Synergistetes and Euryarchaeota during the co-digestion. A significant increase in <I>Syntrophomonas</I> (0.18–11%), <I>Sporanaerobacter</I> (0.14–6%) and <I>Propionispira</I> (0.02–19%) was observed during co-digestion, which substantiated their importance in acetogenesis. Among methanogenic Archaea, the dominance of <I>Methanosaeta</I> (94%) at the beginning of co-digestion was gradually replaced by <I>Methanosarcina</I> (0.52–95%)<I>.</I> The absence/relatively low abundance of syntrophic acetate oxidizers and hydrogenotrophic methanogens, and dominance of acetoclastic methanogens suggested that methane generation during co-digestion of FOG was predominantly conducted through acetoclastic pathway led by <I>Methanosarcina</I>.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The addition of fats, oil and grease enhanced ultimate methane production by 217%. </LI> <LI> Firmicutes, Bacteriodetes, Synergistetes and Euryarchaeota were greatly increased. </LI> <LI> Dominance of <I>Methanosaeta</I> was replaced by <I>Methanosarcina</I> at the end of digestion. </LI> <LI> Methane was predominantly generated through acetoclastic pathway by <I>Methanosarcina</I>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Development of orodispersible tablets of taste masked rizatriptan benzoate using hydroxypropyl b cyclodextrin

Urmila N. Dungarwal,Sanjay B. Patil 한국약제학회 2016 Journal of Pharmaceutical Investigation Vol.46 No.6

The objective of the present study was to prepare orodispersible tablets of rizatriptan benzoate using hydroxypropyl b cyclodextrin (HPbCD) to mask the bitter taste. Taste-masked complex of rizatriptan was prepared with HPbCD by kneading, and analyzed for drug content, FTIR, DSC and bitterness test. Tablets were prepared by direct compression using crospovidone as superdisintegrant. The tablets were evaluated for weight variation, mechanical strength, in vitro disintegration time, wetting time, water absorption ratio, and in vitro release characteristics. The complex showed effective taste masking as compared to plain drug. Hardness and friability data indicated good mechanical strength of tablets. The tablets dispersed rapidly in 35 to 71 s with faster release rate of rizatriptan benzoate. The stability studies for 3 months showed no significant changes in quality of tablets. Hence the present studies indicated the abilities of HPbCD for taste masking and improving the dissolution profile of rizatriptan benzoate after complexation.

Confinement of nano CdS in designated glass: a novel functionality of quantum dot–glass nanosystems in solar hydrogen production

Kale, Bharat B.,Baeg, Jin-Ook,Apte, Sanjay K.,Sonawane, Ravindra S.,Naik, Sonali D.,Patil, Kashinath R. Royal Society of Chemistry 2007 Journal of materials chemistry Vol.17 No.40

<P>The present work is the investigation of our novel approach to designing quantum dot–glass nanosystems by confining nano CdS in designated glass and the first employment of such a quantum dot system in solar hydrogen production. The CdS quantum dots were grown in a special glass matrix, which involved a sequence of steps. The obtained glass was of uniformly bright yellow in color and the bulk glass was pulverized to a fine powder of micron size particles. The glass powder was characterized structurally and morphologically. X-Ray diffraction and electron diffraction patterns reveal a hexagonal crystallite system for the CdS quantum dots. Field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray fluorescence spectroscopy and chemical leaching with HCl studies demonstrate that the 2.5 nm size CdS quantum dots distribute homogeneously in a monodispersed form in the glass domain and on the surface with a “partially embedded exposure” configuration. This disposition imparts an excellent photostability against photocorrosion and also a facile catalytic function. Therefore, even a very small amount of CdS quantum dots (0.005 g per gram of glass powder) is able to photodecompose H<SUB>2</SUB>S under visible light (<I>λ</I> ≥ 420 nm) both in alkaline and pure aqueous media and produce solar hydrogen with markedly high quantum yields of 17.5 and 11.4%, respectively at 470 nm. Salient features like reusability after simple washing, corrosionless-stability and remarkable catalytic activity of this quantum dot–glass nanosystem are brought forth by our novel catalyst design and are much acclaimed in large scale solar H<SUB>2</SUB> production.</P> <P>Graphic Abstract</P><P>CdS quantum dots (∼2.5 nm) in a “partially embedded exposure” configuration were grown in a special glass matrix. This nanosystem was employed for the first time for the photocatalytic production of H<SUB>2</SUB> under visible light. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=b708269j'> </P>

SYNTHESIS OF METASTABLE WURTZITE CZTS NCs AND THEIR TRANSFORMATION INTO KESTERITE CZTS ABSORBER LAYER FOR SOLAR CELL APPLICATION

Uma Ghorpade,Mahesh Suryawanshi,Seung Wook Shin,K. V. Gurav,S. A. Patil,B. S. Pawar,M. G. Gang,Sanjay Kolekar,Jin Hyeok Kim 한국신재생에너지학회 2014 AFORE Vol.2014 No.-