Structural reconstruction of germanosilicate frameworks by controlled hydrogen reduction

Yue Ma; Hao Xu; Xue Liu; Mingming Peng; Wenting Mao; Lu Han; Jingang Jiang; Peng Wu

doi:10.1039/c8cc09294j

Structural reconstruction of germanosilicate frameworks by controlled hydrogen reduction

Chemical Communications ◽

10.1039/c8cc09294j ◽

2019 ◽

Vol 55 (13) ◽

pp. 1883-1886 ◽

Cited By ~ 2

Author(s):

Yue Ma ◽

Hao Xu ◽

Xue Liu ◽

Mingming Peng ◽

Wenting Mao ◽

...

Keyword(s):

Metal Clusters ◽

Hydrogen Reduction ◽

Hydrogen Atmosphere ◽

Water Washing

Calcined UTL-type germanosilicate was firstly reduced in a hydrogen atmosphere at an appropriate temperature. Then, air-calcination and water-washing procedures were performed to remove the Ge metal clusters or crystals originated from the reduction of skeleton germanium(iv) to yield pure zeolite phase of two daughter structures analogous to IPC-2 and IPC-6.

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Development of a Novel Metal Epitaxy Method towards Ni Based Electro-magnetic Hybrid Systems

MRS Proceedings ◽

10.1557/proc-0962-p09-04 ◽

2006 ◽

Vol 962 ◽

Author(s):

Akifumi Matsuda ◽

Masayasu Kasahara ◽

Takahiro Watanabe ◽

Wakana Hara ◽

Sei Otaka ◽

...

Keyword(s):

Thin Film ◽

Epitaxial Film ◽

Hydrogen Reduction ◽

Selective Reduction ◽

Hydrogen Atmosphere ◽

Oxide Thin Film ◽

Single Crystal Substrate ◽

Crystal Substrate ◽

Oxide Substrate ◽

Electro Magnetic

ABSTRACTThe epitaxial Ni (111) thin film on the oxide substrate could be obtained by a novel epitaxy method, employing pulsed laser deposition (PLD) of NiO (111) epitaxial film on the sapphire (α-Al2O3single crystal) substrate and successive hydrogen reduction of NiO. The NiO (111) epitaxial film was deposited on the sapphire (0001) substrate at room-temperature by PLD, and then reduced into the Ni epitaxial film by annealing (300 °C to 500 °C) in the hydrogen-atmosphere. On the other hand, the polycrystalline Ni metal thin film was obtained by reduction of the polycrystalline NiO film, indicating necessity of epitaxial growth for the precursor oxide thin film in the metal epitaxy. The present epitaxy method suggests the possible formation of [Ni/α-Al2O3] epitaxial multilayer via selective reduction of oxide multilayer.

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ChemInform Abstract: METAL CLUSTERS IN CATALYSIS. IV. CATALYTIC HYDROGEN REDUCTION OF CARBON MONOXIDE TO ALKANES

Chemischer Informationsdienst ◽

10.1002/chin.197621129 ◽

1976 ◽

Vol 7 (21) ◽

pp. no-no

Author(s):

M. G. THOMAS ◽

B. F. BEIER ◽

E. L. MUETTERTIES

Keyword(s):

Carbon Monoxide ◽

Metal Clusters ◽

Hydrogen Reduction ◽

Catalytic Hydrogen

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Metal clusters in catalysis. IV. Catalytic hydrogen reduction of carbon monoxide to alkanes

Journal of the American Chemical Society ◽

10.1021/ja00421a059 ◽

1976 ◽

Vol 98 (5) ◽

pp. 1296-1297 ◽

Cited By ~ 83

Author(s):

M. G. Thomas ◽

B. F. Beier ◽

E. L. Muetterties

Keyword(s):

Carbon Monoxide ◽

Metal Clusters ◽

Hydrogen Reduction ◽

Catalytic Hydrogen

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Hydrogen reduction mechanisms of ilmenite between 823 and 1353 K

Journal of Materials Research ◽

10.1557/jmr.1991.0574 ◽

1991 ◽

Vol 6 (3) ◽

pp. 574-584 ◽

Cited By ~ 28

Author(s):

R.A. Briggs ◽

A. Sacco

Keyword(s):

Hydrogen Reduction ◽

Oxygen Removal ◽

Hydrogen Atmosphere ◽

Iron Film ◽

Diffusion Limitations ◽

Reduction Mechanisms ◽

Shrinking Core ◽

Conversion Time ◽

Core Reduction

In situ gravimetric measurements and microscopic examinations were used to determine the mechanisms of oxygen removal from synthetic ilmenite disks between 823 and 1353 K. Under a hydrogen atmosphere, iron was observed to form a layer of low porosity on the surface of samples early in the reduction. This created diffusion limitations for hydrogen to the reaction front and for the escape of water vapor. A shrinking core reduction model, modified to include the growth of this iron film, was capable of predicting the conversion-time relationships of ilmenite samples. An activation energy of 43.2 ± 2.6 kcal/gmole was determined to be representative of reaction control over the temperature range 823–1023 K.

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Production and STEM examination of controlled-size silver clusters

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075488 ◽

1983 ◽

Vol 41 ◽

pp. 338-339

Author(s):

M. A. Listvan ◽

R. P. Andres

Keyword(s):

Cluster Size ◽

Metal Clusters ◽

Experimental Parameter ◽

Carbon Films ◽

Metal Species ◽

Silver Clusters ◽

Free Jet ◽

Size Dependent ◽

Cluster Properties ◽

Controllable Size

Knowledge of the function and structure of small metal clusters is one goal of research in catalysis. One important experimental parameter is cluster size. Ideally, one would like to produce metal clusters of regulated size in order to characterize size-dependent cluster properties.A source has been developed which is capable of producing microscopic metal clusters of controllable size (in the range 5-500 atoms) This source, the Multiple Expansion Cluster Source, with a Free Jet Deceleration Filter (MECS/FJDF) operates as follows. The bulk metal is heated in an oven to give controlled concentrations of monomer and dimer which were expanded sonically. These metal species were quenched and condensed in He and filtered to produce areosol particles of a controlled size as verified by mass spectrometer measurements. The clusters were caught on pre-mounted, clean carbon films. The grids were then transferred in air for microscopic examination. MECS/FJDF was used to produce two different sizes of silver clusters for this study: nominally Ag6 and Ag50.

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