Controlling Interfacial Curvature in Nanoporous Silica Films Formed by Evaporation-Induced Self-Assembly from Nonionic Surfactants. II. Effect of Processing Parameters on Film Structure

Langmuir ◽  
2007 ◽  
Vol 23 (8) ◽  
pp. 4268-4278 ◽  
Author(s):  
Vikrant N. Urade ◽  
Luis Bollmann ◽  
Jonathan D. Kowalski ◽  
Michael P. Tate ◽  
Hugh W. Hillhouse
2008 ◽  
Author(s):  
Lanfang Yao ◽  
Fengqin Lu ◽  
Chunxiao Yue ◽  
Fujiang Xie ◽  
Feifei Guan

Soft Matter ◽  
2019 ◽  
Vol 15 (40) ◽  
pp. 8077-8083 ◽  
Author(s):  
Jessica C. Tom ◽  
Christian Appel ◽  
Annette Andrieu-Brunsen

Stimuli-responsive mesoporous silica films were prepared by evaporation-induced self-assembly through the physical entrapment of a functional block copolymer structuring agent, which simultaneously serves to functionalise the mesopore.


2002 ◽  
Vol 728 ◽  
Author(s):  
Kui Yu ◽  
Bernd Smarsly ◽  
Jeffrey Brinker

AbstractMesostructured silica/diblock films with a 3D arrangement of spherical domains (bcc) were prepared through evaporation-induced self-assembly (EISA) using polystyrene-blockpoly( ethylene oxide) diblock copolymers as structure-directing agents and TEOS (Si(OCH2CH3)4) and/or MTES (Si(OCH2CH3)3CH3) as silica precursors. A detailed small angle x-ray scattering (SAXS) analysis of the calcined mesoporous films showed that, in contrast to recently reported studies, no additional microporosity due to the PEO was observed, indicating that the PEO block formed a layer at the interface between the PS domain and the silica matrix and thus contributed to the mesopore volume. These mesostructured porous silica films are believed to be the first in respect of isolated spheres with a 3D array distributed in a silica matrix without additional microporosity and with MTES as silica precursor. Such closed-cell mesostructured porous materials with high porosity and controllable hydrophobicity can be excellent candidates for low dielectric (K) insulator materials.


Materials ◽  
2013 ◽  
Vol 6 (4) ◽  
pp. 1467-1484 ◽  
Author(s):  
Ioanna Andreou ◽  
Heinz Amenitsch ◽  
Vlassis Likodimos ◽  
Polycarpos Falaras ◽  
Petros Koutsoukos ◽  
...  

2002 ◽  
Vol 726 ◽  
Author(s):  
Uraka Lavrenèiè-Štangar ◽  
Michael Puchberger ◽  
Nicola Hüsing

AbstractSugar-based amphiphilic molecules are used as templates in the sol-gel processing of thin silica films. The films are prepared relying on solvent evaporation-induced self-assembly during dip-coating in a humidity controlled chamber. Different surfactants, such as the commercially available alkyl glycosides (e.g. n-octyl β-D-glucopyranoside and n-dodecyl β-D-maltopyranoside), are compared with respect to their ability to cooperatively self-assemble in alcoholic silicate solutions. The larger polar headgroup (maltose) decreases the critical packing parameter and thus beneficially influences the formation of a favorable hexagonal phase over the lamellar phase, which is formed with the glucose-based surfactant. The inorganic-organic composite films show a strong influence on the humidity during their synthesis. For nonstructured films, ordering could be achieved by exposing the as-deposited films to a high humidity for several hours. The final material is characterized by X-ray diffraction, nitrogen sorption and solid state NMR techniques.


Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 274
Author(s):  
Shih-Jyun Shen ◽  
Demei Lee ◽  
Yu-Chen Wu ◽  
Shih-Jung Liu

This paper reports the binary colloid assembly of nanospheres using spin coating techniques. Polystyrene spheres with sizes of 900 and 100 nm were assembled on top of silicon substrates utilizing a spin coater. Two different spin coating processes, namely concurrent and sequential coatings, were employed. For the concurrent spin coating, 900 and 100 nm colloidal nanospheres of latex were first mixed and then simultaneously spin coated onto the silicon substrate. On the other hand, the sequential coating process first created a monolayer of a 900 nm nanosphere array on the silicon substrate, followed by the spin coating of another layer of a 100 nm colloidal array on top of the 900 nm array. The influence of the processing parameters, including the type of surfactant, spin speed, and spin time, on the self-assembly of the binary colloidal array were explored. The empirical outcomes show that by employing the optimal processing conditions, binary colloidal arrays can be achieved by both the concurrent and sequential spin coating processes.


2004 ◽  
Vol 812 ◽  
Author(s):  
Nobutoshi Fujii ◽  
Kazuhiro Yamada ◽  
Yoshiaki Oku ◽  
Nobuhiro Hata ◽  
Yutaka Seino ◽  
...  

AbstractPeriodic 2-dimensional (2-D) hexagonal and the disordered pore structure silica films have been developed using nonionic surfactants as the templates. The pore structure was controlled by the static electrical interaction between the micelle of the surfactant and the silica oligomer. No X-ray diffraction peaks were observed for the disordered mesoporous silica films, while the pore diameters of 2.0-4.0 nm could be measured by small angle X-ray scattering spectroscopy. By comparing the properties of the 2-D hexagonal and the disordered porous silica films which have the same porosity, it is found that the disordered porous silica film has advantages in terms of the dielectric constant and Young's modulus as well as the hardness. The disordered porous silica film is more suitable for the interlayer dielectrics for ULSI.


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