SwePub - search: WFRF:(Lewis Dewi W.)

Enumeration	Reference	Cover	Find
1.	Cubillas, Pablo, et al. (author) Spiral Growth on Nanoporous Silicoaluminophosphate STA-7 as Observed by Atomic Force Microscopy 2009 In: Crystal Growth & Design. - : American Chemical Society (ACS). - 1528-7483 .- 1528-7505. ; 9:9, s. 4041-4050 Journal article (peer-reviewed)abstract Atomic force microscopy was used to study the surface of STA-7 crystals. STA-7 is a silicoaluminophosphate, nanoporous solid formed by interlinked double six ring units (D6R). Observations showed the formation of three distinct types of spirals at tow supersaturation conditions. The {001} face shows spirals with isotropic shapes and a Burgers vector of 0.9 nm, which corresponds to one D6R or one unit cell along the < 001 > direction. The {100} face contains two distinct types of spirals. The first has a Burgers vector of 0.9 rim, or half a unit cell along < 100 >. This dislocation produces a change in the ""stacking"" sequence of the D6Rs generating all overgrowth with the AEI structure. The second type is an interlaced spiral and is generated by a dislocation with a Burgers vector of 1.8 nm or one unit cell, leading to the formation of two substeps each with a different growth anisotropy. This anisotropy is directed by the shape of the substep and the energetics of template attachment. The preponderance of a surface coating of a secondary phase will have significant consequences on applications reliant on intracrystalline diffusion, such as catalysis, where, owing to diffusion limitations, the outermost structure dominates the functional properties.

Cubillas, Pablo, et al. (author)
Spiral Growth on Nanoporous Silicoaluminophosphate STA-7 as Observed by Atomic Force Microscopy
2009
In: Crystal Growth & Design. - : American Chemical Society (ACS). - 1528-7483 .- 1528-7505. ; 9:9, s. 4041-4050
Journal article (peer-reviewed)abstract
- Atomic force microscopy was used to study the surface of STA-7 crystals. STA-7 is a silicoaluminophosphate, nanoporous solid formed by interlinked double six ring units (D6R). Observations showed the formation of three distinct types of spirals at tow supersaturation conditions. The {001} face shows spirals with isotropic shapes and a Burgers vector of 0.9 nm, which corresponds to one D6R or one unit cell along the < 001 > direction. The {100} face contains two distinct types of spirals. The first has a Burgers vector of 0.9 rim, or half a unit cell along < 100 >. This dislocation produces a change in the ""stacking"" sequence of the D6Rs generating all overgrowth with the AEI structure. The second type is an interlaced spiral and is generated by a dislocation with a Burgers vector of 1.8 nm or one unit cell, leading to the formation of two substeps each with a different growth anisotropy. This anisotropy is directed by the shape of the substep and the energetics of template attachment. The preponderance of a surface coating of a secondary phase will have significant consequences on applications reliant on intracrystalline diffusion, such as catalysis, where, owing to diffusion limitations, the outermost structure dominates the functional properties.

Träfflista för sökning "WFRF:(Lewis Dewi W.) "

Refine your search