Kinetic improvement of H2 absorption and desorption properties in Mg/MgH2 by using niobium ethoxide as additive

ABSTRACTSingle-phase KNbO3 was prepared using bimetallic alkoxides. Potassium-niobium ethoxide, KNb(OC2H5)6, and potassium-niobium propoxide, KNb(OC3H7)6, were synthesized and subsequently hydrolyzed using several water concentrations. Potassium-deficient particles were rapidly precipitated when higher water concentrations were used and this resulted in the formation of a multiphase material after calcination. In contrast, single-phase KNbO3 powders could be prepared by two methods: (1) hydrolysis of KNb(OC3H7)6/propanol solutions using 1 mole water (per mole of propoxide) added as a water/propanol solution and (2) hydrolysis of KNb(OC2H5)6,/ethanol solutions using 1 mole of water (per mole of ethoxide) added as a water/methanol solution. The latter method was also used to form thin films of KNbO3.

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MOCVD deposition of epitaxial lithium niobate, LiNbO3, thin films using the single source precursor lithium niobium ethoxide, LiNb(OEt)6

Chemistry of Materials ◽

10.1021/cm00032a002 ◽

1993 ◽

Vol 5 (8) ◽

pp. 1056-1058 ◽

Cited By ~ 19

Author(s):

Alex A. Wernberg ◽

Henry J. Gysling

Keyword(s):

Thin Films ◽

Lithium Niobate ◽

Single Source ◽

Single Source Precursor ◽

Niobium Ethoxide

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Evolution Of Molecular Structure In Alkoxide-Derived Lithium Niobate

MRS Proceedings ◽

10.1557/proc-180-669 ◽

1990 ◽

Vol 180 ◽

Cited By ~ 8

Author(s):

Dennis J. Eichorst ◽

D. A. Payne

Keyword(s):

Heat Treatment ◽

Lithium Niobate ◽

Structural Changes ◽

Sol Gel ◽

Lithium Oxide ◽

Structural Rearrangements ◽

Raman Spectroscopic ◽

Amorphous Network ◽

Niobium Ethoxide ◽

Gel Processing

ABSTRACTStructural rearrangements during the sol-gel processing of lithium niobate were investigated by FTlR and Raman spectroscopic methods. The reaction of lithium ethoxide with niobium ethoxide resulted in the formation of a bimetallic alkoxide, LiNb(OEt)6 , which could be crystallized from solution. Single crystals were comprised of helical polymeric units consisting of niobium octahedra linked by lithium in tetrahedral (distorted) coordination. Successive crystallizations from solution allowed for the enhanced purification of the alkoxide precursor. Hydrolysis of the bimetallic alkoxide resulted in the formation of an amorphous network structure, which contained niobium-oxygen octahedral units modified by lithium. Heat-treatment facilitated structural rearrangements for the niobium environment, which allowed for the formation of the lithium niobate crystal structure. Further heat-treatment above 700°C resulted in structural changes associated with lithium oxide volatility.

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Sol-Gel Preparation and Characterization of Niobia thin Films for Catalytic Sensor Applications

MRS Proceedings ◽

10.1557/proc-346-553 ◽

1994 ◽

Vol 346 ◽

Cited By ~ 1

Author(s):

Rosibel Ochoa ◽

Raul Miranda

Keyword(s):

Thin Films ◽

Gas Sensors ◽

Sol Gel ◽

Acid Sites ◽

Lewis Acid Sites ◽

Sensor Applications ◽

Donor Acceptor ◽

Gel Preparation ◽

Niobium Ethoxide

ABSTRACTThin films of niobium pentoxide were deposited on quartz plates by spin-coating a solution of niobium ethoxide in ethanol. The films were tested as potential selective gas sensors by exposing them to various reducing environments. It was found that they were selective and sensitive to ammonia. This sensitivity was attributed to the formation of donor-acceptor complexes between chemisorbed ammonia and Lewis acid sites on the solid.

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Crystal structure of lithium niobium ethoxide (LiNb(OCH2CH3)6: a precursor for lithium niobate ceramics

Inorganic Chemistry ◽

10.1021/ic00333a003 ◽

1990 ◽

Vol 29 (8) ◽

pp. 1458-1459 ◽

Cited By ~ 75

Author(s):

Dennis J. Eichorst ◽

Kevin E. Howard ◽

David A. Payne ◽

Scott R. Wilson

Keyword(s):

Crystal Structure ◽

Lithium Niobate ◽

Niobium Ethoxide

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Nb-doped TiO2 Thin Films Prepared through TiCl4 Treatment for Improvement of Their Carrier Transport Property

MRS Advances ◽

10.1557/adv.2019.425 ◽

2019 ◽

Vol 4 (49) ◽

pp. 2665-2671

Author(s):

Takaki Kimura ◽

Kan Hachiya ◽

Takashi Sagawa

Keyword(s):

Thin Films ◽

Carrier Transport ◽

Rutile Phase ◽

X Ray Diffraction ◽

Tio2 Thin Films ◽

X Ray ◽

Hall Effect Measurements ◽

Acidic Conditions ◽

Nb Doping ◽

Niobium Ethoxide

ABSTRACTNb-doped TiO2 thin-films were prepared on fluorine-doped tin oxide (FTO) coated glass directly with niobium ethoxide and TiCl4 in water under the acidic conditions with several concentrations of HCl at 70-90 °C for 45 minutes or 1 hour followed by rinsing with water and annealing at 100 °C for 1 hour. Thin films of 0-1% Nb-doped TiO2 with rutile phase on FTO were obtained, which were confirmed through X-ray diffraction analyses and measurements of energy dispersive X-ray spectroscopy (EDS). Scanning electron microscopy observations equipped with EDS revealed that higher growth temperature over 90 °C is required for doping of Nb. While higher concentration of HCl resulted in much amount of Nb-doping. Band gap of rutile TiO2 gradually reduced from 3.3 eV to 3.23 eV through Nb-doping from 0% to 1%, which were estimated from uv-vis absorption spectroscopic analyses. Hall effect measurements by taking van der Pauw method confirmed that 2.26 times increase of the carrier density and 1.78 times enhancement of the conductivity have been achieved in the case of 1% Nb-doping.

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Enhanced photocatalytic hydrogen evolution from water by niobate single molecular sheets and ensembles

Chemical Communications ◽

10.1039/c4cc04726e ◽

2014 ◽

Vol 50 (89) ◽

pp. 13702-13705 ◽

Cited By ~ 23

Author(s):

Keizo Nakagawa ◽

Tiantian Jia ◽

Weiran Zheng ◽

Simon Michael Fairclough ◽

Masahiro Katoh ◽

...

Keyword(s):

Hydrothermal Synthesis ◽

Hydrogen Evolution ◽

Bottom Up ◽

Photocatalytic Hydrogen Evolution ◽

Niobium Ethoxide

We report single molecular sheets of niobate prepared by a simple bottom-up approach using hydrothermal synthesis of niobium ethoxide with the aid of triethanolamine as a structural modifier.

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A novel route for the synthesis of Sr1−xBaxNb2O6 thin films

Journal of Materials Research ◽

10.1557/jmr.1995.2404 ◽

1995 ◽

Vol 10 (10) ◽

pp. 2404-2407 ◽

Cited By ~ 7

Author(s):

A. Kashani ◽

M.S. Tomar ◽

E. Dayalan

Keyword(s):

Thin Films ◽

Spin Coating ◽

Annealing Temperature ◽

Precursor Solution ◽

Crystalline Material ◽

Silicon Substrates ◽

Silicon Structure ◽

Current Voltage ◽

Capacitance Voltage ◽

Niobium Ethoxide

Stoichiometric Sr1−xBaxNb2O6 (SBN) powder and thin films were prepared by a chemical method. The starting materials were niobium ethoxide and the hydroxides of strontium and barium. Powders were obtained by evaporation of the precursor solution, and thin films were deposited by spin coating. Annealing temperature required to obtain complete conversion to the crystalline material was about 700 °C. Stoichiometric polycrystalline films of Sr1−xBaxNb2O6 were deposited on quartz and silicon substrates. Leakage current-voltage and the capacitance-voltage measurements on a metal/SBN/n-silicon structure show a diode-type characteristic.

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