Synthesis of Ce-Ni based nanofiber as novel catalyst for hydrogen production from sodium borohydride hydrolysis

( Ashif Tamboli ),( Avinash Chaugule ),김헌 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.1

The cerium-nickel loaded on titanium nanofibers were fabricated by simple electrospinning technique for hydrogen production. The catalytic activity of derived composite oxides after calcinations was studied at different parametric conditions. The prepared nanofibers were characterized by the SEM, EDX, FTIR, XRD, BET and TEM technique. The catalytic activities results showed that the activity of catalyst is due to the synergic affect of cerium and nickel composite oxide. The activation energy and recycling ability of prepared nanofiber was evident a beneficial effect of cerium in the catalytic activity for hydrogen production.

Synthesis of cerium and nickel doped titanium nanofibers for hydrolysis of sodium borohydride

Tamboli, Ashif H.,Gosavi, S.W.,Terashima, Chiaki,Fujishima, Akira,Pawar, Atul A.,Kim, Hern Elsevier 2018 CHEMOSPHERE - Vol.202 No.-

<P><B>Abstract</B></P> <P>A recyclable titanium nanofibers, doped with cerium and nickel doped was successfully synthesized by using sol-gel and electrospinning method for hydrogen generation from alkali free hydrolysis of NaBH<SUB>4</SUB>. The resultant nanocomposite was characterized to find out the structural and physical-chemical properties by a series of analytical techniques such as FT-IR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), SEM (scanning electron microscope), EDX (energy-dispersive X-ray spectroscopy),N<SUB>2</SUB> adsorption-desorption and BET (Brunauer–Emmett–Teller), etc. The results revealed that cerium and nickel nanoparticles were homogeneously distributed on the surface of the TiO<SUB>2</SUB> nanofibers due to having similar oxidation state and atomic radium of TiO<SUB>2</SUB>nanofibers with CeO<SUB>2</SUB> and NiO for the effective immobilization of metal ions. The NiO doped catalyst showed superior catalytic performance towards the hydrolysis reaction of NaBH<SUB>4</SUB> at room temperature. These catalysts have ability to produce 305 mL of H<SUB>2</SUB> within the time of 160 min at room temperature. Additionally, reusability test revealed that the catalyst is active even after five runs of hydrolytic reaction, implying the as-prepared NiO doped TiO<SUB>2</SUB> nanofibers could be considered as a potential candidate catalyst for portable hydrogen fuel system such as PEMFC (proton exchange membrane fuel cells).</P> <P><B>Highlights</B></P> <P> <UL> <LI> A recyclable metal doped TiO<SUB>2</SUB> electrospun nanofibers was successfully synthesized. </LI> <LI> Beadles nanofibers and uniform distribution of doped metal facilitate stability to catalyst. </LI> <LI> The metal doped catalyst showed superior activity for hydrolysis of NaBH<SUB>4</SUB>. </LI> <LI> The metal doped TiO<SUB>2</SUB> catalyst could be used repeatedly without significant loss in activity. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Catalytic developments in the direct dimethyl carbonate synthesis from carbon dioxide and methanol

Tamboli, Ashif H.,Chaugule, Avinash A.,Kim, Hern Elsevier 2017 Chemical Engineering Journal Vol.323 No.-

<P><B>Abstract</B></P> <P>The present review compiles the recently published literature for the single step dimethyl carbonate (DMC) synthesis from carbon dioxide (CO<SUB>2</SUB>) and methanol. The various routes of DMC synthesis are also discussed in short with their advantages and disadvantages in order to distinguish the merits of direct DMC synthesis route. Next, the major applications of DMC such as in electrochemistry, as fuels additive, as solvent and building block in organic synthesis are described. The major problems in the direct DMC synthesis route such as low yield, reaction rate, thermodynamic limitations and hydrolysis of produced DMC are also pointed out. Furthermore, the significance of fabricating an effective dehydrating agent for the removal of water from the reaction is narrated for the enhancement of DMC yield. The type of catalyst materials based on their nature i.e. metal carbonates, tin-based catalysts, metal oxides, organic catalysts and polymer based materials, etc. used for title reaction are separately discussed in details. The varieties of dehydrating agents and their role in DMC production is explained with the help of most recent reported literature.</P> <P><B>Highlights</B></P> <P> <UL> <LI> DMC are commonly used as fuel additive, in electrochemistry and organic synthesis. </LI> <LI> This study presents an overview of advances in direct DMC synthesis from CO<SUB>2</SUB> and methanol. </LI> <LI> It also summarizes the challenges such as necessity of dehydrating agents. </LI> <LI> And the uses of various catalysts to address challenges like low yield and thermodynamic limitations. </LI> </UL> </P>

Cerium-Nickel doped biopolymer-ionic Liquid composite membranes: amino functionalized novel catalyst for direct dimethyl carbonate synthesis

( Ashif Tamboli ),김헌 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.0

Chitosan solutions were prepared by dissolving 7 g of chitosan in 100 ml of 90% acetic acid solution and stirring overnight. IL doped chitosan films were obtained by adding different concentrations of IL (100, 120, 150 and 200 wt %) in chitosan solution and mixed thoroughly. In this study, our goal was the development of solid chitosan/ IL films doped with Ce-Ni nanoparticles and utilized in DMC synthesis as catalyst. To our knowledge no previous report has been published on chitosan IL polymer doped Ce/Ni NPs catalyst synthesis and its DMC production application.

Glycerol functionalized imidazolium tricationic room temperature ionic liquids synthesis and application for 2-azidoalcohol synthesis from epoxide

( Avinash Chaugule ),( Ashif Tamboli ),김헌 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.1

The new tricationic room temperature ionic liquids (RTILs) based on 3-methylimidazolium were synthesized form glycerol. The RTILs presented interesting physicochemical properties at different temperature. The Lewis acidity of prepared ionic liquid was determined by IR spectroscopy. The [GLY(mim)₃][OMs] IL showed highest Lewis acidic behavior. The catalytic activity and reusability of these tricationic RTILs were investigated for 2-azidoalcohol synthesis from epoxide and sodium azide. The prepared tricationic RTILs in presence of water as proton source exhibited high catalytic activity compared to monotri-cationc ILs.

CuCl₂@Poly-IL catalyzed carboxylation of terminal alkynes through CO₂ utilization

Chaugule, Avinash A.,Tamboli, Ashif H.,Kim, Hern Elsevier 2017 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.326 No.-

<P><B>Abstract</B></P> <P>The carboxylation of terminal alkynes from CO<SUB>2</SUB> is a most attractive route in green chemistry point of view. Herein, we synthesized a novel CuCl<SUB>2</SUB>@Poly-GLY(1-Vim)<SUB>3</SUB>(OMs)<SUB>3</SUB> catalyst and employed to the efficient carboxylation of terminal alkynes (phenyl carboxylate esters) by utilizing CO<SUB>2</SUB> under 4MPa, at 40°C. In presence of catalyst, various terminal alkynes found to be easily reacting with CO<SUB>2</SUB> and organic halide to affording a high yield of carboxylic ester. Moreover, CuCl<SUB>2</SUB>@Poly-GLY(1-vim)<SUB>3</SUB>(OMs)<SUB>3</SUB> catalyst is capable to obtain a high yield of corresponding carboxylic ester using various types organic halide. Furthermore, CuCl<SUB>2</SUB>@Poly-GLY(1-vim)<SUB>3</SUB>(OMs)<SUB>3</SUB> catalyst able to easily recover and reuse for four times without any obvious loss in catalytic activity. The catalytic reactivity of CuCl<SUB>2</SUB>@Poly-GLY(1-vim)<SUB>3</SUB>(OMs)<SUB>3</SUB> catalyst is explained on the basis of predicted mechanism.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Preparation of Poly-GLY(mim)<SUB>3</SUB>(OMs)<SUB>3</SUB>. </LI> <LI> Synthesis of Cu@Poly-GLY(mim)<SUB>3</SUB>(OMs)<SUB>3</SUB> catalyst. </LI> <LI> Efficient carboxylation of terminal alkyne. </LI> <LI> Catalyst able to reuse for four times. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Ionic liquid as a catalyst for utilization of carbon dioxide to production of linear and cyclic carbonate

Chaugule, Avinash A.,Tamboli, Ashif H.,Kim, Hern Elsevier 2017 Fuel Vol.200 No.-

<P><B>Abstract</B></P> <P>In this review, primary focus on the ionic liquid (IL) catalysts and related catalytic systems for utilization of carbon dioxide to a production of linear as well as cyclic carbonate, and describes the innovative progress observed during last ten years. This review covers trend of various catalysts starting from first conventional ILs (tetrabutylammonium bromide and imidazolium IL) to the latest metal containing IL systems employed for the efficient production of dimethyl carbonate. Moreover, recent advances in DMC production also summarizes using the catalysts which contain novel super base facilitated tri-cationic IL systems. Similarly, cyclic carbonate synthesis reveals the benefits of using IL based catalyst on the verity of different supporting materials such as alumina, silica, carbon nanotubes, magnetic nanoparticles, poly(ethylene glycol), polystyrene, cellulose, and chitosan. The summary of ammonium, phosphonium and both functionalized and unfunctionalized imidazolium salts indicates that the turnover frequency for epoxide and propylene oxide enhances under mild reaction condition. Overall, it is clear that metal ions or super base in the combination of ILs can improve the conversions and the presence of hydroxyl, carboxyl, and other functional groups will enhance the yield multiple folds through hydrogen bonding interaction.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Synthesis of Co₃O₄ macrocubes catalyst using novel chitosan/urea template for hydrogen generation from sodium borohydride

Tomboc, Gracita Raquel M.,Tamboli, Ashif H.,Kim, Hern Elsevier 2017 ENERGY Vol.121 No.-

<P><B>Abstract</B></P> <P>Co<SUB>3</SUB>O<SUB>4</SUB> catalyst with porous macrocubes structure were one pot formulated by hydrothermal treatment of chitosan/urea/Co(NO<SUB>3</SUB>)<SUB>2</SUB>·6H<SUB>2</SUB>O mixtures at 180 °C for 8 h and then calcined at different temperatures for 4 h. Chitosan and urea are both compounds containing amino group, which made them different from the previous supporting materials. In this study, chitosan was the major template in the solution and determined the shape of the Co<SUB>3</SUB>O<SUB>4</SUB> catalyst while urea played a major support to cobalt (II) nitrate hexahydrate during crystal growth of the catalyst. The prepared materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectrum (FT-IR), UV–vis Absorption Spectrum and BET technique. A remarkably high hydrogen generation rate of 1497.55 ml<SUB>H2</SUB> min<SUP>−1</SUP> g<SUB>cat</SUB> <SUP>−1</SUP> was obtained from the hydrolysis of 2 wt % NaBH<SUB>4</SUB> solution with 0.02 g catalyst at 25 °C. The catalytic activity of the as-prepared sample was examined for hydrolysis reaction of sodium borohydride (NaBH<SUB>4</SUB>) at different temperatures, catalyst amount and NaBH<SUB>4</SUB> concentration. The results reveal that the average crystallite size, macrocubes thickness, surface properties and catalytic activity of Co<SUB>3</SUB>O<SUB>4</SUB> macrocubes could be controlled by varying the mass ratio of chitosan/urea to cobalt concentration.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesized Co<SUB>3</SUB>O<SUB>4</SUB> catalyst thru hydrothermal treatment using chitosan/urea. </LI> <LI> Optimal ratio of Co(NO<SUB>3</SUB>)<SUB>2</SUB>·6H<SUB>2</SUB>O to urea is 1:10 and calcination temperature at 700 °C. </LI> <LI> Co<SUB>3</SUB>O<SUB>4</SUB> catalyst has macrocubes structure w/sponge surface & crystal size is 42.35 nm. </LI> <LI> A remarkably high HGR of 1497.55 ml<SUB>H2</SUB> min<SUP>−1</SUP> g<SUB>cat</SUB> <SUP>−1</SUP> was obtained. </LI> <LI> Activation energy was calculated using the Arrhenius eq'n & result was 47.97 KJ/mol. </LI> </UL> </P>

A super hydrophilic modification of poly(vinylidene fluoride) (PVDF) nanofibers: By in situ hydrothermal approach

Sheikh, Faheem A.,Zargar, Mohammad Afzal,Tamboli, Ashif H.,Kim, Hern Elsevier 2016 APPLIED SURFACE SCIENCE - Vol.385 No.-

<P><B>Abstract</B></P> <P>Nanofibers fabricated from Poly(vinylidene fluoride) (PVDF) possesses potential applications in the field of filtrations, because of their excellent resistance towards harsh chemicals. However, the hydrophobicity restricts its further application. In this work, we focus on optimal parameters for post-electrospun tethering of Poly(vinyl alcohol) (PVA) as superhydrophilic domain onto each individual PVDF nanofibers by exploiting the in situ hydrothermal approach. The results indicated an increase in nanofiber diameters due to coating of PVA and improved surface wettability of PVDF nanofibers. The tensile tests of nanofibers indicated that mechanical properties of PVDF nanofibers could be sharply tuned from rigid to ductile. Furthermore, the studies strongly suggest that in situ hydrothermal treatment of post-electrospun nanofibers can improve the water contact angle and these nanofibers can be used in varied applications (e.g., in water purification systems).</P> <P><B>Highlights</B></P> <P> <UL> <LI> PVA coated PVDF nanofibers can be easily prepared by hydrothermal treatment. </LI> <LI> The inherent hydrophobicity of PVDF nanofibers can be changed to hydrophilic. </LI> <LI> The hydrogen bonding interaction can induce the crystalline conformation of PVDF. </LI> <LI> Resultant nanofibers have significant improvement in the tensile strength. </LI> <LI> Prepared membranes promise to aid in filtration due to involvement of PVA coating. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Ionic liquid based Cu₂S@C catalyst for effective coupling of diaryl diselenide with aryl halides under ligand-free conditions

Chaugule, Avinash A.,Pawar, Atul A.,Tamboli, Ashif H.,Bandal, Harshad A.,Chung, Wook-Jin,Kim, Hern Elsevier 2018 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.351 No.-

<P><B>Abstract</B></P> <P>Diaryl selenide is the main drug candidate today. An efficient, easy and ligand free cross-coupling reaction of aryl halide and diaryl diselenide was carried out by as-prepared copper sulfide functionalized carbon (Cu<SUB>2</SUB>S@C) catalyst. Cu<SUB>2</SUB>S@C catalyst was developed using novel tri-cationic ionic liquid (IL) as a precursor and sulfur source. Catalyst found to having rich content of heteroatoms (S and N) by EDX and Elemental mapping characterization techniques. Effective utilization of catalyst was carried out by synthesis of variety of aryl selenide in excellent yield from readily halides and diaryl diselenides. Active centers in the catalyst provide efficient activation for crosscoupling reaction. Moreover, catalyst where easily reusable for three times without any obvious loss in catalytic activity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Preparation of Poly-GLY(1-vinyl)<SUB>3</SUB>(OMs)<SUB>3</SUB>. </LI> <LI> Synthesis of Cu<SUB>2</SUB>S@C catalyst. </LI> <LI> Efficient synthesis of aryl selenide. </LI> <LI> Catalyst able to reuse for three times. </LI> </UL> </P>