02690nas a2200313   4500008004100000022001400041245011600055210006900171260009500240300001200335490000800347520155000355653003601905653002801941653001101969653003001980653002002010653001802030653000802048100001902056700001702075700001702092700003502109700002702144700003002171700001902201700002602220856013002246       2006                        eng d  a0021-951700aEffect of spacer groups on the performance of MCM-41-supported platinum cluster-derived hydrogenation catalysts0 aEffect of spacer groups on the performance of MCM41supported pla  a525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USAbACADEMIC PRESS INC ELSEVIER SCIENCEcSEP  a332-3390 v2423 a<p>MCM-41 was functionalized with (EtO)(3)SiCH2Cl, (MeO)(3)SiCH2CH2CH2Cl, and (CH3)Cl2SiCH2Cl. The functionalized materials were characterized by solid-state NMR (CPMAS, Si-29 and C-13) and XPS. The NMR data indicate that three new silicon environments were created by(EtO)(3)SiCH2Cl and (MeO)(3)SiCH2CH2CH2Cl, whereas with (CH3)Cl2SiCH2Cl, two new silicon environments were obtained. XPS results from Si 2p core level and the valence band from the material functionalized by (MeO)(3)Si(CH2)(3)Cl was found to be the same as that of the corresponding fresh catalyst (1a), in contrast to that of the materials functionalized by the other two silane reagents. After further functionalization with triethylamine, these materials were used as inorganic anion exchangers to support the cluster anion [Pt-12(CO)(24)](2-). Solid-state NMR (29Si, C-13, N-15) was used to establish the presence of the quaternary ammonium group in the cluster-supported species. Analogous materials were also created using fumed silica as the support, and all of the cluster-supported materials were tested as catalysts for the hydrogenation of methyl pyruvate, acetophenone, nitrobenzene, benzonitrile, ethylacetoacetate, 4-nitrotoluene, cyclohexanone, allyl alcohol, and styrene. The best activity was obtained for the catalyst that had MCM-41 as the support and chloropropyl as the spacer group. TEM showed that the supports and the spacer groups had observable effects on the platinum crystallite size of the catalysts. (c) 2006 Elsevier Inc. All rights reserved.</p>10afunctionalized inorganic oxides10ahydrogenation catalysts10aMCM-4110aplatinum carbonyl cluster10aSolid-state NMR10aspacer groups10aXPS1 aMaity, Niladri1 aBasu, Susmit1 aMapa, Maitri1 aRajamohanan, Pattuparambil, R.1 aGanapathy, Subramanian1 aGopinath, Chinnakonda, S.1 aBhaduri, Sumit1 aLahiri, Goutam, Kumar  uhttps://library.ncl.res.in/content/effect-spacer-groups-performance-mcm-41-supported-platinum-cluster-derived-hydrogenation-102188nas a2200265   4500008004100000022001400041245012200055210006900177260009500246300001200341490000800353520115600361653004001517653002301557653002601580653002801606653003001634100001701664700001701681700003001698700001801728700001901746700002601765856013101791       2006                        eng d  a0021-951700aMCM-41-supported platinum carbonyl cluster-derived catalysts for asymmetric and nonasymmetric hydrogenation reactions0 aMCM41supported platinum carbonyl clusterderived catalysts for as  a525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USAbACADEMIC PRESS INC ELSEVIER SCIENCEcAPR  a154-1610 v2393 a<p>Anionic platinum carbonyl Cluster ([Pt-12(CO)(24)](2-)) was ion-paired with the 3-chloropropyltrimethoxysilyl-ammonium group chemically bound to the surface of MCM-41. The materials undergo quick decarbonylation and have been characterized before decarbonylation by IR and UV-vis spectroscopy and after decarbonylation by XPS and TEM. They have been used as catalysts for the hydrogenations of methyl pyruvate, acetophenone, nitrobenzene, benzonitrile, and ethylacetoacetate. The support and the quaternary ammonium groups have significant effects on surface platinum concentration, crystallite size, and observed activity. In the hydrogenation of the prochiral substrates methyl pyruvate or acetophenone, the cinchonidine-based catalyst gives significant enantioselectivity under optimum conditions. A kinetic model that includes an enantioselective product-formation step and a hydrogen pressure-dependent step for the deactivation of the enantioselective sites gives reasonable agreement between predicted and observed enantioselectivity. The model is also in accordance with the XPS and TEM data. (c) 2006 Elsevier Inc. All rights reserved.</p>10aasymmetric/non-asymmetric catalysis10aEnantioselectivity10afunctionalized MCM-4110ahydrogenation catalysts10aplatinum carbonyl cluster1 aBasu, Susmit1 aMapa, Maitri1 aGopinath, Chinnakonda, S.1 aDoble, Mukesh1 aBhaduri, Sumit1 aLahiri, Goutam, Kumar  uhttps://library.ncl.res.in/content/mcm-41-supported-platinum-carbonyl-cluster-derived-catalysts-asymmetric-and-nonasymmetric-101987nas a2200157   4500008004100000022001400041245009000055210006900145260007100214300001200285490000700297520137400304100001701678700003001695856010401725       2009                        eng d  a0897-475600aCombustion synthesis of triangular and multifunctional ZnO1-xNx (x <= 0.15) materials0 aCombustion synthesis of triangular and multifunctional ZnO1xNx x  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJAN  a351-3590 v213 a<p>The preparation and characterization of multifunctional ZnO1-xNx (x &lt;= 0.15) via a simple solution combustion method is reported. ZnO1-xNx exhibits visible light absorption, thermal stability, nanometer-/ micrometer-sized triangular particles, and catalytic properties. X-ray diffraction studies of ZnO1-xNx, demonstrate that the lattice oxygen in ZnO is replaced by nitrogen without any major change in the wurtzite structure; however, charge compensation occurs, because of interstitial Zn atoms, as well as oxygen vacancies. Microscopic studies reveal the dominance of nanometer- and micrometer-sized triangles of ZnO1-xNx. UV-visible and Raman spectra indicate a midgap state, derived from N 2p states, and direct Zn-N interaction, respectively. Secondary ion mass spectrometry studies show the presence of N and ZnN species in the bulk and support the direct Zn-N interaction. Electron paramagnetic resonance (EPR) studies indicate the presence of a small amount of defects. Photocatalytic decomposition of rhodamine B, and anisole acylation at room temperature, highlights the effectiveness of ZnO1-xNx to catalysis applications. The aforementioned multifunctional characteristics suggest that ZnO1-xNx might be used in place of conventional ZnO for better control and that it might be explored for further applications in catalysis and optoelectronics.</p>1 aMapa, Maitri1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/combustion-synthesis-triangular-and-multifunctional-zno1-xnx-x-001617nas a2200241   4500008004100000022001400041245007700055210006900132260007100201300001400272490000700286520077800293100001701071700002101088700001901109700002901128700001801157700002201175700001901197700002401216700003001240856010501270       2009                        eng d  a0897-475600aElectronic structure and catalytic study of solid solution of GaN in ZnO0 aElectronic structure and catalytic study of solid solution of Ga  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUL  a2973-29790 v213 a<p>Solid solutions of GaN in ZnO (Zn1-zGaz)(O1-xNx) (x and z &lt;= 0.15) have been prepared by simple solution combustion method, Except for minor changes in the lattice contraction, no significant change in the Wurtzite structure was observed. Raman and secondary ion mass spectrometry results show the direct Zn-N and Ga-N bonds in (Zn1-zGaz)(O1-xNx). Visible light absorption and XPS results demonstrate that N 2p states of nitride occupy the states above the O 2p valence band, and hence a change in optical band gap reduction occurs to similar to 2.5 eV from 3.37 eV for ZnO. Significant nitrogen fixation catalytic activity through NH3 formation has been observed at ambient pressure oil virgin (Zn1-zGaz)(O1-xNx) material, indicating its potential as a catalyst.</p>1 aMapa, Maitri1 aThushara, K., S.1 aSaha, Biswajit1 aChakraborty, Purushottam1 aJanet, C., M.1 aViswanath, R., P.1 aNair, Madhavan1 aMurty, K., V. G. K.1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/electronic-structure-and-catalytic-study-solid-solution-gan-zno-002123nas a2200217   4500008004100000022001400041245011900055210006900174260007100243300001200314490000700326520126200333100001701595700003301612700002001645700001901665700002901684700003101713700003001744856013101774       2010                        eng d  a0897-475600aStructure, electronic structure, optical, and dehydrogenation catalytic study of (Zn1-zInz)(O1-xNx) solid solution0 aStructure electronic structure optical and dehydrogenation catal  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJAN  a565-5780 v223 a<p>Indium and nitrogen codoping in ZnO leads to a solid solution of InN in ZnO with I composition of(Zn1-zInz)(O1-xNx). A simple solution combustion method has been adopted to prepare the above materials in less than 10 min with metal nitrates as the metal loll source and urea as fuel. With reference to ZnO, significant increase in lattice parameters was observed with increasing In-content. However, the In2O3 phase was Observed along with InN for]it content &gt;= 10%. Optical absorption extended into the Visible region, at least LIP to 550 nm, demonstrates an effective reduction of optical band gap due to the formation of solid Solution. A new feature observed just above O2p valence band in X-ray photoelectron spectroscopy (XPS) suggests the creation of N 2p states from InN; the N Is core level XPS result too confirms nitride contribution. Raman spectroscopy and secondary ion mass spectrometry results show direct In-N, Zn-N. and In-N-Zn fragments in (Zn1-zInz)(O1-x,N-x). Catalytic activity explored for Oxidation of 2-butanol to ethyl methyl ketone demonstrates a high selectivity at 350 and 400 degrees C. All of the above characteristics suggest the multifunctional nature of (Zn1-zInz)(O1-xNx) and its potential for other applications.</p>1 aMapa, Maitri1 aSivaranjani, Kumarsrinivasan1 aBhange, Deu, S.1 aSaha, Biswajit1 aChakraborty, Purushottam1 aViswanath, Annamraju, Kasi1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/structure-electronic-structure-optical-and-dehydrogenation-catalytic-study-zn1-zinzo1-xnx-002000nas a2200169   4500008004100000022001400041245013100055210006900186260011000255300001600365490000700381520124000388100002501628700001701653700003001670856013001700       2014                        eng d  a1477-922600aIn1-XGaXN@ZnO: a rationally designed and quantum dot integrated material for water splitting and solar harvesting applications0 aIn1XGaXNZnO a rationally designed and quantum dot integrated mat  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcSEP  a12546-125540 v433 a<p>The highly desirable combination of the visible light absorption properties of In1-xGaxN Quantum dots (QD) along with the multifunctionality of ZnO into a single integrated material was prepared for solar harvesting. This is the first report on InGaN QD integrated with ZnO (InGaN@ZnO), synthesized by a highly reproducible, simple combustion method in 15 min. Structural, microstructural and electronic integration of the nitride and oxide components of InGaN@ZnO was demonstrated by appropriate characterization methods. Self-assembly of InGaN QD is induced in growing nascent zinc oxo nanoclusters taking advantage of the common wurtzite structure and nitrogen incorporation at the expense of oxygen vacancies. Direct integration brings about a single phase structure exhibiting extensive visible tight absorption and high photostability. InGaN@ZnO suggests synergistic operation of tight harvesting and charge conducting components for solar H-2 generation without using any co-catalyst or sacrificial agent, and a promising photocurrent generation at 0 V under visible light illumination. The present study suggests a direct integration of QD with the host matrix and is a potential method to realize the advantages of QDs.</p>1 aRajaambal, Sivaraman1 aMapa, Maitri1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/in1-xgaxnzno-rationally-designed-and-quantum-dot-integrated-material-water-splitting-and-0