02567nas a2200205 4500008004100000022001400041245013300055210006900188260011000257300001400367490000700381520171100388100002102099700001802120700002102138700002702159700002102186700002502207856012902232 2007 eng d a0959-942800aConfinement of nano CdS in designated glass: a novel functionality of quantum dot-glass nanosystems in solar hydrogen production0 aConfinement of nano CdS in designated glass a novel functionalit aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcAUG a4297-43030 v173 a

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 H2S under visible light (lambda >= 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-2 production.

1 aKale, Bharat, B.1 aBaeg, Jin-Ook1 aApte, Sanjay, K.1 aSonawane, Ravindra, S.1 aNaik, Sonali, D.1 aPatil, Kashinath, R. uhttps://library.ncl.res.in/content/confinement-nano-cds-designated-glass-novel-functionality-quantum-dot-glass-nanosystems-002174nas a2200217 4500008004100000022001400041245010000055210006900155260007100224300001600295490000800311520133400319100002501653700002501678700002701703700002601730700002301756700002101779700002901800856012701829 2008 eng d a1932-744700aN-doped TiO2 nanoparticle based visible light photocatalyst by modified peroxide sol-gel method0 aNdoped TiO2 nanoparticle based visible light photocatalyst by mo a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcSEP a14595-146020 v1123 a

The peroxide gel route is employed to synthesize N-doped TiO2 nanoparticles (NP) at low temperature using titanium tetraisopropoxide, ethylmethylamine, and hydrogen peroxide as precursors. Structural studies show anatase phase in the undoped titania NPs as well as at 5 at. % N-doped titania NPs, although with a degree of matrix disorder in the latter case. The annealing of N-doped titania NPs at different temperatures shows that above 400 degrees C nitrogen escapes the O-Ti-O matrix and at 500 degrees C the sample becomes crystalline. Transmission electron microscopy reveals that the particle size is in the range of 20-30 nm for the undoped TiO2 but only 5-10 nm for N-doped TiO2. At higher nitrogen concentration (10 at. %) bubble-like agglomerates form. FTIR and photoluminescence quenching also confirm the incorporation of nitrogen in anatase TiO2. Optical properties reveal an extended tailing of the absorption edge toward the visible region upon nitrogen doping. X-ray photoelectron spectroscopy is used to examine the electronic state of doped nitrogen and the associated possible electronic modification of the TiO2 matrix. Under visible light irradiation the undoped TiO2 NPs do not show any significant photocatalytic activity, as expected; however, the 5 at. % N-doped TiO2 NPs show excellent activity.

1 aJagadale, Tushar, C.1 aTakale, Shrikant, P.1 aSonawane, Ravindra, S.1 aJoshi, Hrushikesh, M.1 aPatil, Shankar, I.1 aKale, Bharat, B.1 aOgale, Satishchandra, B. uhttps://library.ncl.res.in/content/n-doped-tio2-nanoparticle-based-visible-light-photocatalyst-modified-peroxide-sol-gel-002739nas a2200265 4500008004100000022001400041245009000055210006900145260007300214300001200287490000800299520182300307653001702130653001902147653001902166653001302185653001502198653002002213100002602233700002802259700002702287700001902314700002302333856011702356 2010 eng d a0926-860X00aVanadia-titania thin films for photocatalytic degradation of formaldehyde in sunlight0 aVanadiatitania thin films for photocatalytic degradation of form aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcFEB a103-1090 v3743 a

Thin films of vanadia-titania with good adhesion to the substrates have been deposited on various substrates such as glass slides, glass helix and silica raschig rings by simple sol-gel dip coating process using vanadium and titanium peroxide gel. The optimum concentration of vanadia in titania for obtaining good uniform viscous gel was found to be 0.5-4 wt% beyond which the vanadia particles disturb the gel network, resulting in the formation of a gelatinous precipitate. The films of vanadia-titania as well as the dried powder of the bulk gel were characterized by different characterization techniques. Optical characterization by UV-vis spectrophotometer showed a shift in optical absorption wavelength to the visible region that may be due to the incorporation of vanadia into titania structure. The XRD revealed the formation of anatase phase in pure titania as well as titania with up to 2% vanadia loading, whereas formation of rutile as minor phase along with anatase as major phase was observed at higher vanadia loading. The XRD did not show any peaks of vanadia phase up to 5% vanadia loading indicating either incorporation of vanadia into titania structure or high dispersion of amorphous vanadia on titania support. The pure and vanadia doped TiO(2) thin films were evaluated for their photocatalytic activity for degradation of methylene blue as a model pollutant under sunlight. Doping Of V(2)O(5) in TiO(2) showed an increase in the photo-degradation rate of methylene blue by a factor of 3-6.6 times compared to pure TiO(2). The highest rate has been obtained for 4% V(2)O(5)-doped TiO(2) films. Vanadia doped TiO(2) thin films were also found to be very active for photocatalytic degradation of formaldehyde from aqueous solution in sunlight. (c) 2009 Elsevier B.V. All rights reserved.

10aFormaldehyde10aMethylene blue10aPhotocatalysis10aSunlight10aThin films10aV(2)O(5)/TiO(2)1 aAkbarzadeh, Rokhsareh1 aUmbarkar, Shubhangi, B.1 aSonawane, Ravindra, S.1 aTakle, Srikant1 aDongare, Mohan, K. uhttps://library.ncl.res.in/content/vanadia-titania-thin-films-photocatalytic-degradation-formaldehyde-sunlight-003116nas a2200217 4500008004100000022001400041245014200055210006900197260011000266300001400376490000700390520221200397100002602609700002402635700002702659700002202686700002502708700002002733700002102753856012402774 2011 eng d a1463-926200aEcofriendly hydrogen production from abundant hydrogen sulfide using solar light-driven hierarchical nanostructured ZnIn2S4 photocatalyst0 aEcofriendly hydrogen production from abundant hydrogen sulfide u aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJUL a2500-25060 v133 a

It is quite well-known that refineries are producing huge amount of H2S which has been used to produce sulphur and water using the well-known Claus process. This process is not an economically viable process, due to the high-cost chemical process and creates further acute environmental problems. Therefore, we have demonstrated the conversion of poisonous H2S into H-2 using an ecofriendly phocatalysis process which is a green unconventional energy source. We have investigated ecofriendly nanostructured ZnIn2S4 photocatalyst to produce hydrogen from H2S using solar light. We also demonstrate the controlled synthesis of hierarchical nanostructured ZnIn2S4 using a facile hydrothermal method. The morphologies obtained have been greatly influenced by the presence of triethylamine (TEA) with various concentrations during the reaction. Surprisingly, a highly crystalline hexagonal layer structured ZnIn2S4 was obtained instead of cubic spinel. The hierarchical nanostructure, i.e. marigold flower-like morphology, was obtained without any surfactant. The thin and transparent petals self-assembled to form the unique nanostructured marigold flower. The highly crystalline puffy marigold flowers and nanoplates/nanostrips were obtained using TEA-assisted hydrothermal synthesis. Optical study shows the band gap in the range of 2.34-2.48 eV. Considering the band gap in the visible region, ZnIn2S4 is used as photocatalyst for hydrogen production from hydrogen sulphide under solar light which is hitherto unattempted. The constant photocatalytic activity of hydrogen evolution, i.e. 5287 mu mol h(-1), was obtained using such hierarchical nanostructured ZnIn2S4 under visible light irradiation. It is noteworthy that the H-2 evolution rate obtained is much higher compared to earlier reported photocatalysts. Considering the significance of morphologies for photocatalytic application, the formation mechanism has also been furnished. The unique hierarchical nanostructured ZnIn2S4 ternary semiconductor having hexagonal layer will have potential applications in solar cells, LEDs, charge storage, electrochemical recording, thermoelectricity and other prospective electronic and optical devices.

1 aChaudhari, Nilima, S.1 aBhirud, Ashwini, P.1 aSonawane, Ravindra, S.1 aNikam, Latesh, K.1 aWarule, Sambhaji, S.1 aRane, Vilas, H.1 aKale, Bharat, B. uhttps://library.ncl.res.in/content/ecofriendly-hydrogen-production-abundant-hydrogen-sulfide-using-solar-light-driven-0