Records |
Author |
Xu, T.; Nys, J.-P.; Addad, A.; Lebedev, O.I.; Urbieta, A.; Salhi, B.; Berthe, M.; Grandidier, B.; Stievenard, D. |
Title |
Faceted sidewalls of silicon nanowires: Au-induced structural reconstructions and electronic properties |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
11 |
Pages |
115403,1-115403,10 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Si nanowires with a ⟨111⟩ orientation, synthesized by vapor-liquid-solid process with low silane partial pressure reactant and gold as the catalyst, are known to exhibit sawtooth facets containing gold adsorbates. We report herein the study of the nanowire morphology by means of transmission electron microscopy and scanning tunneling microscopy. The nanowires consist of faceted sidewalls. The number of the sidewalls changes from 12 to 6 along the growth axis, giving rise to nanowires with an irregular hexagonal cross section at their base. The sidewalls are covered with Au-rich clusters. Their facets also exhibit atomic structures that reveal the presence of gold, resulting from the diffusion of gold during the growth. Based on these observations, the tapering of the nanowire is found to be related to two contributions: the reduction in the catalyst particle size during the growth and lateral overgrowth from the direct incorporation of Si species onto the nanowire sidewalls. Because the rearrangement of atoms at surfaces and interfaces might affect the growth kinetics, the trigonal symmetry as well as the higher lateral growth rate on the widest sidewalls are explained from the existence of an interfacial atomic structure with two inequivalent parts in the unit cell. Finally, spectroscopic measurements were performed on the major facets and revealed a metallic behavior at 77 K. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000276248800116 |
Publication Date |
2010-03-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
42 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:82273 |
Serial |
1168 |
Permanent link to this record |
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Author |
Ke, X.; Bals, S.; Cott, D.; Hantschel, T.; Bender, H.; Van Tendeloo, G. |
Title |
Three-dimensional analysis of carbon nanotube networks in interconnects by electron tomography without missing wedge artifacts |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
Volume |
16 |
Issue |
2 |
Pages |
210-217 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The three-dimensional (3D) distribution of carbon nanotubes (CNTs) grown inside semiconductor contact holes is studied by electron tomography. The use of a specialized tomography holder results in an angular tilt range of ±90°, which means that the so-called missing wedge is absent. The transmission electron microscopy (TEM) sample for this purpose consists of a micropillar that is prepared by a dedicated procedure using the focused ion beam (FIB) but keeping the CNTs intact. The 3D results are combined with energy dispersive X-ray spectroscopy (EDS) to study the relation between the CNTs and the catalyst particles used during their growth. The reconstruction, based on the full range of tilt angles, is compared with a reconstruction where a missing wedge is present. This clearly illustates that the missing wedge will lead to an unreliable interpretation and will limit quantitative studies |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge, Mass. |
Editor |
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Language |
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Wos |
000276137200011 |
Publication Date |
2010-02-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.891 |
Times cited |
42 |
Open Access |
|
Notes |
Esteem 026019; Fwo; Iap-Vi |
Approved |
Most recent IF: 1.891; 2010 IF: 3.259 |
Call Number |
UA @ lucian @ c:irua:82279 |
Serial |
3642 |
Permanent link to this record |
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Author |
Goffin, A.-L.; Duquesne, E.; Raquez, J.-M.; Miltner, H.E.; Ke, X.; Alexandre, M.; Van Tendeloo, G.; van Mele, B.; Dubois, P. |
Title |
From polyester grafting onto POSS nanocage by ring-opening polymerization to high performance polyester/POSS nanocomposites |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
Volume |
20 |
Issue |
42 |
Pages |
9415-9422 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Polyester-grafted polyhedral oligomeric silsesquioxane (POSS) nanohybrids selectively produced by ring-opening polymerization of ε-caprolactone and L,L-lactide (A.-L. Goffin, E. Duquesne, S. Moins, M. Alexandre, Ph. Dubois, Eur. Polym. Journal, 2007, 43, 4103) were studied as masterbatches by melt-blending within their corresponding commercial polymeric matrices, i.e., poly(ε-caprolactone) (PCL) and poly(L,L-lactide) (PLA). For the sake of comparison, neat POSS nanoparticles were also dispersed in PCL and PLA. The objective was to prepare aliphatic polyester-based nanocomposites with enhanced crystallization behavior, and therefore, enhanced thermo-mechanical properties. Wide-angle X-ray scattering and transmission electron microscopy attested for the dispersion of individualized POSS nanoparticles in the resulting nanocomposite materials only when the polyester-grafted POSS nanohybrid was used as a masterbatch. The large impact of such finely dispersed (grafted) nanoparticles on the crystallization behavior for the corresponding polyester matrices was noticed, as evidenced by differential scanning calorimetry analysis. Indeed, well-dispersed POSS nanoparticles acted as efficient nucleating sites, significantly increasing the crystallinity degree of both PCL and PLA matrices. As a result, a positive impact on thermo-mechanical properties was highlighted by dynamic mechanical thermal analysis. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000283264500017 |
Publication Date |
2010-06-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0959-9428;1364-5501; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
42 |
Open Access |
|
Notes |
Fwo; Iap-6 |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:85784 |
Serial |
1284 |
Permanent link to this record |
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Author |
Neek-Amal, M.; Peeters, F.M. |
Title |
Lattice thermal properties of graphane : thermal contraction, roughness, and heat capacity |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
23 |
Pages |
235437-235437,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using atomistic simulations, we determine the roughness and the thermal properties of a suspended graphane sheet. As compared to graphene, we found that (i) hydrogenated graphene has a larger thermal contraction, (ii) the roughness exponent at room temperature is smaller, i.e., ≃ 1.0 versus ≃ 1.2 for graphene, (iii) the wavelengths of the induced ripples in graphane cover a wide range corresponding to length scales in the range 30125 Å at room temperature, and (iv) the heat capacity of graphane is estimated to be 29.32±0.23 J/mol K, which is 14.8% larger than that for graphene, i.e., 24.98±0.14 J/mol K. Above 1500 K, we found that graphane buckles when its edges are supported in the x-y plane. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000292253400011 |
Publication Date |
2011-06-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
42 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgium Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:90921 |
Serial |
1803 |
Permanent link to this record |
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Author |
Neyts, E.C. |
Title |
PECVD growth of carbon nanotubes : from experiment to simulation |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of vacuum science and technology: B: micro-electronics processing and phenomena |
Abbreviated Journal |
|
Volume |
30 |
Issue |
3 |
Pages |
030803-030803,17 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Nanostructured carbon materials show a tremendous variety in atomic structure, morphology, properties, and applications. As all properties are ultimately determined by the structure of the material, a thorough understanding of the growth mechanisms that give rise to the particular structure is critical. On many occasions, it has been shown that plasma enhanced growth can be strongly beneficial. This review will describe the authors current understanding of plasma enhanced growth of carbon nanotubes, the prototypical example of nanostructured carbon materials, as obtained from experiments, simulations, and modeling. Specific emphasis is put on where experiments and computational approaches correspond, and where they differ. Also, the current status on simulating PECVD growth of some other carbon nanomaterials is reviewed, including amorphous carbon, graphene, and metallofullerenes. Finally, computational challenges with respect to the simulation of PECVD growth are identified. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000305042000010 |
Publication Date |
2012-04-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2166-2746; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
42 |
Open Access |
|
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:97166 |
Serial |
2570 |
Permanent link to this record |
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Author |
Angelomé, P.C.; Heidari Mezerji, H.; Goris, B.; Pastoriza-Santos, I.; Pérez-Juste, J.; Bals, S.; Liz-Marzán, L.M. |
Title |
Seedless synthesis of single crystalline Au nanoparticles with unusual shapes and tunable LSPR in the near-IR |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
24 |
Issue |
7 |
Pages |
1393-1399 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The plasmonic properties of metal nanoparticles have acquired great importance because of their potential applications in very diverse fields. Metal nanoparticles with localized surface plasmon resonances (LSPR) in the near-infrared (NIR, 7501300 nm) are of particular interest because tissues, blood, and water display low absorption in this spectral range, thus facilitating biomedical applications. Cetyltrimethylammonium chloride (CTAC) was used to induce the seedless formation of highly anisotropic, twisted single crystalline Au nanoparticles in a single step. The LSPR of the obtained particles can be tuned from 600 nm up to 1400 nm by simply changing the reaction temperature or the reagents concentrations. The tunability of the LSPR is closely associated with significant changes in the final particle morphology, which was studied by advanced electron microscopy techniques (3D Tomography and HAADF-STEM). Kinetic experiments were carried out to establish the growth mechanism, suggesting that slow kinetics together with the complexation of the gold salt precursor to CTAC are key factors favoring the formation of these anisotropic particles. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000302487500020 |
Publication Date |
2012-03-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
42 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
Call Number |
UA @ lucian @ c:irua:97388 |
Serial |
2959 |
Permanent link to this record |