01169nas a2200181 4500008004100000245007200041210006900113260000800182300001600190490000600206520055800212100001900770700002200789700001900811700002400830700003100854856010200885 2017 eng d00aAmphi-functional mesoporous silica nanoparticles for dye separation0 aAmphifunctional mesoporous silica nanoparticles for dye separati cJUL a14914-149210 v53 aSynthesis of amphi-functional mesoporous silica nanoparticles (similar to 80 nm) by stepwise chemical modifications of outer and inner pore surfaces is reported. These materials display a clear "Janus" like character and are able to selectively and completely separate hydrophobic dyes form a mixture of dyes. Our results clearly suggest a clear partition of more hydrophobic dyes into the pores from a mixture of two dyes. In addition this material displays a remarkable recycling ability for 10 cycles with up to similar to 99% dye removal from water.1 aShinde, Pravin1 aGupta, Sayam, Sen1 aSingh, Baljeet1 aPolshettiwar, Vivek1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/amphi-functional-mesoporous-silica-nanoparticles-dye-separation01939nas a2200181 4500008004100000245008500041210006900126260000800195300002800203490000800231520127700239100003201516700001401548700001901562700003101581700002801612856011701640 2017 eng d00aInterfacial-active polymer nanoparticles, their assemblies, and SERS application0 aInterfacialactive polymer nanoparticles their assemblies and SER cDEC aArticle Number: 17002610 v2183 aIn this work, surface-active polymer nanoparticles as well as polymer-polymer and polymer-metal nanoassembly particles are synthesized, and different parameters such as their size, morphologies, and assembling strength are studied. Nanoassembly particles are attractive because of the coupled properties with a large surface to volume ratio. A key challenge is to produce the core-shell polymer nanoparticles via single-step processes. To address this concern, here, microfluidics approach and precise interfacial reaction strategies are used, and hence different types of surface layered polymer nanoparticles are obtained in one-step processes. An inner core material is hydrophobic, whereas a hydrophilic surface layer (in situ formed during the polymerization process) swells in the aqueous environment. Moreover, three different reaction setups (batch, flow, and in situ) are applied in order to architect the nanoassembling hierarchical structures via layer-by-layer strategy. On the other side, polymer-metal nanoassembly particles as well as metal catalyzed metal deposited four layered nanoassembly particles of tuned size and compositions are produced. It is shown that these particles can be used as nanosensor particles for surface-enhanced Raman spectroscopy.1 aVisaveliya, Nikunjkumar, R.1 aLi, Xiang1 aKnauer, Andrea1 aPrasad, Bhagavatula, L. V.1 aKohler, Johann, Michael uhttp://library.ncl.res.in/content/interfacial-active-polymer-nanoparticles-their-assemblies-and-sers-application01997nas a2200205 4500008004100000245010500041210006900146260000800215300001200223520123300235100002201468700002201490700002101512700001801533700002901551700003101580700003101611700001801642856013101660 2017 eng d00aMicelles versus Ribbons: how congeners drive the self-assembly of acidic sophorolipid biosurfactants0 aMicelles versus Ribbons how congeners drive the selfassembly of  cMAR a643-6523 a

Sophorolipids (SLs), a class of microbially derived biosurfactants, are reported by different research groups to have different self-assembled structures (either micelles or giant ribbons) under the same conditions. Here we explore the reasons behind these contradictory results and attribute these differences to the role of specific congeners that are present in minute quantities. We show that a sample composed of a majority of oleic acid (C18:1) sophorolipid in the presence of only 0.5 % (or more) of congeners with stearic acid (C18:0) or linoleic acid (C18:2) results in the formation of micelles that are stable over long periods of time. Conversely, the presence of only 10 to 15 % of congeners with a stearic acid chain gives fibrillar structures instead of micelles. To study the mechanisms responsible, oleic acid SLs devoid of any other congeners were prepared. Very interestingly, this sample can self-assemble into either micelles or fibers depending on minute modifications to the self-assembly conditions. The findings are supported by light scattering, small-angle X-ray scattering, transmission electron microscopy under cryogenic conditions, high-pressure liquid chromatography, and NMR spectroscopy.

1 aDhasaiyan, Prabhu1 aLe Griel, Patrick1 aRoelants, Sophie1 aRedant, Emile1 aVan Bogaert, Inge, N. A.1 aPrevost, Sylvain, Francois1 aPrasad, Bhagavatula, L. V.1 aBaccile, Niki uhttp://library.ncl.res.in/content/micelles-versus-ribbons-how-congeners-drive-self-assembly-acidic-sophorolipid-biosurfactants01312nas a2200169 4500008004100000022001400041245015600055210006900211260000800280300001600288490000700304520062800311100002000939700002300959700003100982856012901013 2017 eng d a1528-748300aMicrowave assisted batch and continuous flow synthesis of palladium supported on magnetic nickel nanocrystals and their evaluation as reusable catalyst0 aMicrowave assisted batch and continuous flow synthesis of pallad cAUG a5163–51690 v173 aPalladium nanocrystals (NCs) supported on nickel NCs (Pd/Ni) were synthesized in a continuous flow manner by the microwave-assisted method in the presence and absence of oleylamine. Parameters optimized for batch experiments were considered while performing continuous flow synthesis. The Pd/Ni NCs synthesized in the presence of oleylamine displayed good catalytic activity for hydrogenation of aromatic nitro compounds, and those bearing alkene, and alkyne moieties. The ferromagnetic character of the supporting nickel NCs allowed the recovery of the catalyst and these recovered catalysts could be reused several times.1 aNikam, Arun, V.1 aKulkarni, Amol, A.1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/microwave-assisted-batch-and-continuous-flow-synthesis-palladium-supported-magnetic-nickel02340nas a2200229 4500008004100000245007100041210006900112260000800181300001400189490000800203520158700211100002101798700002701819700003101846700002701877700001901904700001501923700002801938700001801966700002401984856010202008 2017 eng d00aNanoparticle assembly: a perspective and some unanswered questions0 aNanoparticle assembly a perspective and some unanswered question cAPR a1635-16410 v1123 aIn early 2016, the Royal Society of Chemistry arranged a meeting on the topic 'Nanoparticle Assemblies: from Fundamentals to Applications' which was hosted at IIT-Bombay, Mumbai. The meeting brought several leading nanoscience and nanotechnology researchers to India and is only the second Faraday Discussions meeting to have been held in the country. The papers presented at the meeting and the resulting active discussions have been summarized in a Faraday Discussion issue(1). The broad range of topics discussed at the meeting led to an understanding on where we stand in the field of nanoparticle assembly, and also enunciated some of the outstanding fundamental and practical issues that remain to be resolved before these ideas can be applied to practical situations. Driven by these ideas, here we focus on four topics/questions: (i) Can we achieve function-driven design of nanoparticle assemblies? (ii) What is the minimal information needed to build a desired assembly? (iii) How complex a structure can one build? How can one make it responsive? What are the relative roles of equilibrium versus dynamics in the assembly process, and are we at a point where we can now pursue active assembly as a viable mode for creating complex assemblies? (iv) What are the applications that are being targeted and what are the barriers to implementation? In this perspective, we do not present an exhaustive survey of the vast literature in this area, but indicate overarching themes/questions that require immediate attention, largely based on the discussions at the Mumbai meeting.1 aKumar, Sanat, K.1 aKumaraswamy, Guruswamy1 aPrasad, Bhagavatula, L. V.1 aBandyopadhyaya, Rajdip1 aGranick, Steve1 aGang, Oleg1 aManoharan, Vinothan, N.1 aFrenkel, Daan1 aKotov, Nicholas, A. uhttp://library.ncl.res.in/content/nanoparticle-assembly-perspective-and-some-unanswered-questions01110nas a2200169 4500008004100000245006400041210006300105260000800168300001400176490000800190520054700198100002600745700001800771700003100789700002500820856009500845 2017 eng d00aNickel-catalyzed direct synthesis of dialkoxymethane ethers0 aNickelcatalyzed direct synthesis of dialkoxymethane ethers cAUG a1153-11590 v1293 aA simple and efficient method for the preparation of dialkoxymethane ethers (oxymethylene ethers) from alcohols and paraformaldehyde in the presence of commercially available nickel(II) salt is described. The reaction proceeds readily under neutral, solvent-free conditions using paraformaldehyde as a C-1 source. The present strategy has a broad substrate scope including aliphatic (both primary and secondary) and aromatic alcohols and provides a benign method for the preparation of symmetrical dialkoxymethanes in good yields (up to 89%).1 aSubaramanian, Murugan1 aBera, Abhijit1 aPrasad, Bhagavatula, L. V.1 aBalaraman, Ekambaram uhttp://library.ncl.res.in/content/nickel-catalyzed-direct-synthesis-dialkoxymethane-ethers01208nas a2200145 4500008004100000022001400041245009700055210006900152260000800221490000700229520065500236100001800891700003100909856012200940 2018 eng d a0250-470700a2D molecular precursor for a one-pot synthesis of semiconducting metal sulphide nanocrystals0 a2D molecular precursor for a onepot synthesis of semiconducting  cOCT0 v413 a2D molecular materials, namely, metal alkyl thiolates, have been used as a single-source precursor for the synthesis of semiconducting metal sulphide nanocrystals (NCs) by thermal decomposition. These 2D molecular precursors have all the ingredients required for metal sulphide synthesis (metal source, sulphur source and protecting ligand). In this study, we demonstrate a simple and general solvothermal decomposition' approach for the synthesis of high-quality , PbS, CdS, MnS and ZnS NCs. The size of the NC can also be controlled by changing the decomposition temperature. Furthermore, the optical properties of the NCs have also been studied. 1 aBera, Abhijit1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/2d-molecular-precursor-one-pot-synthesis-semiconducting-metal-sulphide-nanocrystals01950nas a2200169 4500008004100000022001500041245008300056210006900139260000800208300001600216490000700232520135500239100002301594700002801617700003101645856010401676 2018 eng d a 0743-746300a Ligand-solvent compatibility: the unsung hero in the digestive ripening story0 aLigandsolvent compatibility the unsung hero in the digestive rip cNOV a13680-136890 v343 a

Digestive ripening (DR) is a process where a polydisperse nanocrystal (NC) system is converted into a monodisperse one with the aid of thermal heating of NCs in the presence of an excess surface-active organic ligand called digestive ripening agent (DRA) and a solvent. Here, we demonstrate that the solvent-DRA compatibility influences the final size and size distribution of the NCs in a significant manner. Accordingly, in this study, using the DR of gold NCs as the test case with alkanethiol (decanethiol/C10HT) and fluorinated thiol (1H,1H,2H,2H-perfluorodecanethiol/C10FT) as DRA's and toluene and alpha,alpha,alpha-trifluoro-toluene (TFT) and their combination as solvents, we clearly establish that alkanethiols result in best-quality NCs after DR in toluene while the fluorinated thiols provide reasonably monodispersed NCs in TFT. Our results also ascertain that even when DR is carried out in a mixture of solvents, as long as the compatible solvent is the major component, the DR process results in reasonably monodisperse NCs. As soon as the amount of uncompatible solvent exceeds a threshold limit, there is perceptible increase in the polydispersity of the NCs. We conclude that the polarity of the solvent, which affects the buildup of ligated atoms/clusters, plays a key role in controlling the size distributions of the NCs.

1 aShimpi, Jayesh, R.1 aChaudhari, Vijay, Raman1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/ligand-solvent-compatibility-unsung-hero-digestive-ripening-story01791nas a2200181 4500008004100000022001400041245011600055210006900171260000900240300001400249490000700263520112100270100002201391700002101413700001801434700003101452856012601483 2018 eng d a0743-746300apH- and time-resolved in situ SAXS study of self-assembled twisted ribbons formed by elaidic acid sophorolipids0 apH and timeresolved in situ SAXS study of selfassembled twisted  cFEB  a2121-21310 v343 a

Conditions that favor the helical structure formation in structurally similar sophorolipids (SLs), that is, elaidic acid SLs (having a trans double bond between the C9 and C10 positions of the alkyl chain) and stearic acid SLs (no double bond), are presented here. The helical self-assembled structures formed by elaidic acid SLs were independent of pH and also were mediated by a micellar intermediate. On the other hand, the stearic acid SLs formed helical structures under low pH condition only. Astonishingly, the formation routes were found to be different, albeit the molecular geometry of both SLs is similar. Even if a conclusive mechanistic understanding must await further work, our studies strongly point out that the noncovalent weak interactions in elaidic acid SLs are able to overcome the electrostatic repulsions of the sophorolipid carboxylate groups at basic pH and facilitating the formation of helical structures. On the other hand, the hydrophobic interactions in stearic acid SLs endow the helical structures with extra stability, making them less vulnerable to dissolution upon heating.

1 aDhasaiyan, Prabhu1 aPrevost, Sylvain1 aBaccile, Niki1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/ph-and-time-resolved-situ-saxs-study-self-assembled-twisted-ribbons-formed-elaidic-acid01753nas a2200181 4500008004100000022001400041245014100055210006900196260000800265300001200273490000700285520106100292100001701353700002001370700002501390700003101415856012501446 2018 eng d a1144-054600aPreparation of metal oxide supported catalysts and their utilization for understanding the effect of a support on the catalytic activity0 aPreparation of metal oxide supported catalysts and their utiliza cJAN a402-4100 v423 a

A convenient way of anchoring transition metal nanoparticles (palladium, platinum, rhodium and ruthenium) onto metal oxide supports (magnesium oxide and zirconium oxide) by means of a modified sol-gel technique is demonstrated. Use of toluene dispersed, ligand protected pre-synthesized nanoparticles during sol-gel synthesis delivered size-controlled, spatially distributed, well-adhered transition metal nanoparticles (MNPs) on metal oxide supports. The catalytic activities of these supported nanoparticles were tested for the p-nitro phenol reduction reaction. It was observed that the reaction kinetics were crucially dependent on the catalyst support and MNP size. The influence of the magnesium oxide and zirconium oxide supports towards the catalytic performance of the anchored transition MNPs was probed using cyclic voltammetry and the differences in the same were attributed to the support-induced modification in the electronic properties of the MNPs. Our results indicated that magnesium oxide is a better support than zirconium oxide.

1 aSeth, Jhumur1 aDubey, Prashant1 aChaudhari, Vijay, R.1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/preparation-metal-oxide-supported-catalysts-and-their-utilization-understanding-effect01318nas a2200229 4500008004100000022001400041245015400055210006900209260000800278300001200286490000600298520046800304653002000772653002300792653002100815653002400836653002300860100002500883700002500908700003100933856012400964 2020 eng d a2194-428800aMechanistic aspects of methanol electro-oxidation reaction through cyclic voltammetry: is it correct to blame carbon monoxide for catalyst poisoning?0 aMechanistic aspects of methanol electrooxidation reaction throug cMAY a19009550 v83 a

The mechanism of the methanol oxidation reaction is revisited using systematic cyclic voltammetric studies. These studies clearly indicate that the peak during the cathodic scan belongs mainly to electro-oxidation of the carbon monoxide, and that only a fraction of this carbon monoxide remains adsorbed on the electrode, contrary to what previous reports suggested. More details can be found in article number by Bhagavatula L. V. Prasad and co-workers.

10acarbon monoxide10acyclic voltammetry10aelectrocatalysts10aelectrode poisoning10aMethanol oxidation1 aDeshpande, Pooja, S.1 aChaudhari, Vijay, R.1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/mechanistic-aspects-methanol-electro-oxidation-reaction-through-cyclic-voltammetry-it00637nas a2200157 4500008004100000022001400041245013000055210006900185260000800254300001000262490000600272100001800278700002600296700003100322856012600353 2020 eng d a2168-048500aSolvent-less solid state synthesis of dispersible metal and semiconducting metal sulfide nanocrystals (vol 6, pg 12006, 2018)0 aSolventless solid state synthesis of dispersible metal and semic cNOV a170000 v81 aBera, Abhijit1 aBusupalli, Balanagulu1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/solvent-less-solid-state-synthesis-dispersible-metal-and-semiconducting-metal-sulfide-001915nas a2200145 4500008004100000245012900041210006900170260000800239300001400247490000700261520140500268100002401673700003101697856004101728 2022 eng d00aSelective electro-oxidation of phenol to 1,4-hydroquinone employing carbonaceous electrodes: surface modification is the key0 aSelective electrooxidation of phenol to 14hydroquinone employing cJAN a2518-25250 v463 aThe oxidation of phenol leading to 1,4-hydroquinone with high conversion, remarkable selectivity and an excellent yield (87% isolated) has been accomplished under electrolytic conditions in an aqueous medium employing carbon-based electrodes. To achieve this, various factors such as electrode stability, repeatability, and the type of product formed by the electrochemical oxidation of phenol have been investigated using cyclic voltammetry first and then organic transformations under optimized conditions were accomplished by constant current electrolysis. The voltammetric data clearly show that electrochemically generated intermediates passivate the surface of the typically used electrodes, leading to a decrease in their activity, which is a major problem concerning the transformation of phenol electro-oxidation to an industrially adaptable process. In this work, it is established that such difficulties could be circumvented using surface modified carbonaceous electrodes having disordered graphene-like structures and oxygen functional groups. It is also demonstrated that surface modified reticulated vitreous carbon (RVC) based electrodes could be used for electro-oxidation of phenol at a reasonably large scale. The electrolysis conditions have been optimized based on the mechanistic understanding leading to remarkable conversion of phenol with 87% selectivity to 1,4-hydroquinone.1 aBaravkar, Mayur, D.1 aPrasad, Bhagavatula, L. V. uhttp://dx.doi.org/10.1039/D1NJ04640C02372nas a2200217 4500008004100000022001400041245011800055210006900173260000800242300001600250490000700266520156800273653001701841653003101858653002101889653003701910653003201947100002101979700003102000856012302031 2023 eng d a1944-824400aAlloying with Mn enhances the activity and durability of the CoPt catalyst toward the methanol oxidation reaction0 aAlloying with Mn enhances the activity and durability of the CoP cMAY a26554-265620 v153 a

To improve the catalytic performance and durability ofPt catalystsused for the methanol oxidation reaction (MOR) in direct methanolfuel cells (DMFCs), alloying of Pt with other transition metals suchas Ru, Co, Ni, and Fe is considered an effective approach. Despitethe significant progress made in the preparation of bimetallic alloysand their utilization for MOR, improving the activity and durabilityof the catalysts to make them commercially viable remains a stiffchallenge. In this work, trimetallic Pt100-x (MnCo)( x ) (16 < x < 41) catalysts were successfully synthesized via borohydridereduction followed by hydrothermal treatment at 150 & DEG;C. The electrocatalyticperformance of the synthesized trimetallic Pt100-x (MnCo)( x ) (16 < x < 41) catalysts toward MOR was studied using cyclicvoltammetry and chronoamperometry. The results affirm that all Pt100-x (MnCo)( x ) (16 < x < 41) alloys have superior MOR activityand durability as compared to bimetallic PtCo alloys and commerciallyavailable Pt/C (comm. Pt/C) catalysts. Among all the compositionsstudied, the Pt60Mn1.7Co38.3/C catalystexhibited superior mass activity (1.3 and 1.9 times higher than thoseof Pt81Co19/C and comm. Pt/C, respectively)toward MOR. Furthermore, all the newly synthesized Pt100-x (MnCo)( x )/C (16 < x < 41) catalysts showed better CO tolerance when comparedwith comm. Pt/C. This improved performance of the Pt100-x (MnCo)( x )/C (16 < x < 41) catalyst can be attributed to the synergisticeffect of Co and Mn on the Pt lattice.

10aCO tolerance10adirect methanol fuel cells10aelectrocatalysis10amethanol oxidation reaction(MOR)10atrimetallic alloy catalysts1 aDeshpande, Pooja1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/alloying-mn-enhances-activity-and-durability-copt-catalyst-toward-methanol-oxidation01854nas a2200157 4500008004100000022001400041245010600055210006900161260000800230300001400238490000700252520125400259100002701513700003101540856012501571 2023 eng d a0306-001200aSurface functionalization of inorganic nanoparticles with ligands: a necessary step for their utility0 aSurface functionalization of inorganic nanoparticles with ligand cAPR a2573-25950 v523 a

The importance of organic ligands in protecting inorganic nanoparticles and thus imparting the needed stabilization as colloidal dispersions was realised many years ago. Currently, the rational preparation of such nanoparticles with designed organic molecules/ligands resulting in the formation of functional nanoparticles (FNPs) that are tuned for a specific application is an area of immense research interest. The preparation of such FNPs for a desired application requires a clear understanding of the interactions at the nanoparticle (NP)-ligand and ligand-solvent interfaces, and demands a deep appreciation of the surface science and coordination chemistry. In this tutorial review, we briefly explore the evolution of surface-ligand chemistry and inform the readers that, apart from protecting the surface, ligands can modulate the physico-chemical properties of the underlying inorganic NPs as well. This review further presents the design principles for the rational preparation of such FNPs, where one or more ligand shells can be added to the nanoparticle surface, thereby improving the adaptability and amenability of the NP exterior towards the environment in which they are present, as required for a specific application.

1 aBhattacharjee, Kaustav1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/surface-functionalization-inorganic-nanoparticles-ligands-necessary-step-their-utility02168nas a2200193 4500008004100000022001400041245013500055210006900190260000900259300001400268490000700282520143800289100002701727700002201754700001901776700002301795700003101818856012501849 2023 eng d a1744-683X00aTopological phases in nanoparticle monolayers: can crystalline, hexatic, and isotropic-fluid phases coexist in the same monolayer?0 aTopological phases in nanoparticle monolayers can crystalline he cOCT  a7271-72800 v193 a

Topological phases are stable configurations of matter in 2-dimensions (2D) formed via spontaneous symmetry breaking. These play a crucial role in determining the system properties. Though a number of fundamental studies on topological phase transitions and topological defect dynamics have been conducted with model colloidal systems (typically microns in size), the same is lacking on nanoparticle monolayers (NPMLs, typically made of ligand-coated sub-ten nanometer particles). Here, we show that in an evaporation-driven self-assembly process, the three topological phases, namely crystalline, hexatic, and isotropic-fluid phases, can coexist within the same NPML. We associate this coexistence with the local variation in particle size, which can be described by a unique frequency parameter (p(25)), quantifying the fraction of NPs that has size deviation greater than or equal to 25% of the mean size (where the deviation,f is defined as f = ((|Size-mean|)/mean)). The p(25)-values for the three phases are distinctly different: crystalline arrangement occurs when p(25) < similar to 0.02, while a hexatic phase exists for 0.02 <= p(25) <= 0.1. For p(25) Z 0.1, the isotropic-fluid phase occurs. Following KTHNY-theory, we further numerically extrapolate the occurrence of each phase to the accumulated excess planar strain in the NPML due to the presence of various topological defects in the structures.

1 aBhattacharjee, Kaustav1 aVaidya, Salil, S.1 aPathak, Tushar1 aShimpi, Jayesh, R.1 aPrasad, Bhagavatula, L. V. uhttp://library.ncl.res.in/content/topological-phases-nanoparticle-monolayers-can-crystalline-hexatic-and-isotropic-fluid