Closed-Cell Mesostructured Porous Silica Films Templated by PS-b-PEO Without Additional Microporosity

2002 ◽  
Vol 728 ◽  
Author(s):  
Kui Yu ◽  
Bernd Smarsly ◽  
Jeffrey Brinker
Keyword(s):  
Self Assembly ◽  
Diblock Copolymers ◽  
Porous Silica ◽  
Silica Matrix ◽  
High Porosity ◽  
Silica Films ◽  
Low Dielectric ◽  
Closed Cell ◽  
Evaporation Induced Self Assembly ◽  
Saxs Analysis

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.

Luminescence of rhodamine B doped in silica films by evaporation-induced self-assembly

2008 ◽  
Author(s):  
Lanfang Yao ◽  
Fengqin Lu ◽  
Chunxiao Yue ◽  
Fujiang Xie ◽  
Feifei Guan
Keyword(s):  
Rhodamine B ◽  
Self Assembly ◽  
Silica Films ◽  
Evaporation Induced Self Assembly

Thermal stability of low dielectric constant porous silica films

2005 ◽  
Vol 87 (26) ◽  
pp. 262909 ◽  
Author(s):  
L. Esposito ◽  
G. Ottaviani ◽  
E. Carollo ◽  
M. Bacchetta
Keyword(s):  
Thermal Stability ◽  
Dielectric Constant ◽  
Porous Silica ◽  
Low Dielectric Constant ◽  
Silica Films ◽  
Low Dielectric ◽  
Thermal Stability Of

Photodegradation Activity of Poly(ethylene oxide-b-ε-caprolactone)-Templated Mesoporous TiO2 Coated with Au and Pt

2020 ◽  
Vol 20 (8) ◽  
pp. 5276-5281 ◽  
Author(s):  
Wei-Cheng Chu ◽  
Jeonghun Kim ◽  
Minjun Kim ◽  
Abdulmohsen Ali Alshehri ◽  
Yousef Gamaan Alghamidi ◽  
...  
Keyword(s):  
Ethylene Oxide ◽  
Self Assembly ◽  
Diblock Copolymers ◽  
Charge Carriers ◽  
Nanocomposite Films ◽  
Soft Template ◽  
X Ray Scattering ◽  
Evaporation Induced Self Assembly ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Mesoporous TiO2 films are synthesized through evaporation-induced self-assembly using poly(ethylene oxide-b-ε-caprolactone) diblock copolymers as a soft-template. Using small-angle X-ray scattering and scanning electron microscopy, we investigate the effect of the TiO2/PEO-b-PCL ratio on the resulting nanoarchitectonic structure. After sputter-coating Au and Pt layers, these Au/TiO2 and Pt/TiO2 nanocomposite films display drastically enhanced photodegradation of rhodamine 6G under ultraviolet irradiation, due to the metal films inhibiting the rapid recombination of photogenerated charge carriers.

Synthesis and Characterization of Ordered Mesoporous Carbon/Silica Hybrid Thin Films

2008 ◽  
Vol 6 (1) ◽  
Author(s):  
Xiaoxian Wang ◽  
Tiehu Li ◽  
Qilang Lin ◽  
Dawei Wang ◽  
Tingkai Zhao
Keyword(s):  
Electron Microscopy ◽  
Pore Size ◽  
Self Assembly ◽  
Sol Gel ◽  
Dip Coating ◽  
Silica Matrix ◽  
Nanocomposite Films ◽  
Evaporation Induced Self Assembly ◽  
Hybrid Thin Films ◽  
Silica Nanocomposite

Carbon/silica nanocomposite films with a hexagonal P6mm structure were fabricated directly by the oxidation and carbonization of surfactant/silica nanocomposite films, which were obtained by a dip-coating technique through a combination of sol-gel and evaporation-induced self-assembly. The as-synthesized nanocomposite films were characterized by scanning electron microscopy, X-ray diffraction, transmission electron microscopy and N2 adsorption-desorption. These analyses reveal that the carbon/silica nanocomposite films, with a narrow pore size distribution of mesopores, have an ordered symmetric structure. The pore sizes of this hybrid film can be controlled within a certain range by changing the carbonization temperature. In addition, the films are composed of a continuous silica matrix and a continuous carbon coating in about 1 nm adhered well to the silica matrix. The formation of carbon coatings from surfactant acts as a framework support to prevent the pore size of the silica matrix from shrinking.

Synthesis and Characterization of Magnetic Mesoporous Ɣ-FE2O3/SIO2

2014 ◽  
Vol 879 ◽  
pp. 128-133
Author(s):  
Nur Shuhada Shaari ◽  
Suhaina Mohd Ibrahim ◽  
Farinaa Md Jamil ◽  
Zuhana Ahmad Zubir ◽  
A.M. Abdullah ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Iron Oxide ◽  
Self Assembly ◽  
Quantum Interference ◽  
Silica Matrix ◽  
Synthesis And Characterization ◽  
Vibrating Sample Magnetometer ◽  
Superconducting Quantum Interference Device ◽  
Evaporation Induced Self Assembly

Magneticmesoporousɣ-Fe2O3/SiO2 synthesized using an evaporation-induced self-assembly (EISA) approach. The non-ionictriblock copolymer P123 was used as surfactant template with various amounts of iron oxide (1.8g-2.4g) and varied during the synthesis. Characterizations of the surface area and magnetic properties for prepared materials were done using N2-sorption analyses, and a superconducting quantum interference device interfaced with a vibrating sample magnetometer (SQUID-VSM) respectively. From this study, N2-sorption analysis indicated that most of the ɣ-Fe2O3domains of several nanometres were embedded in the silica matrix. In addition, the obtained magneticmesoporouscomposite which contains 2.3g amount ofiron oxide has revealedhigher magnetism saturation value of (4.564 emu/g) compared to other prepared samples which been evaluated by VSM analysis.

scholarly journals Fabrication and in situ functionalisation of mesoporous silica films by the physical entrapment of functional and responsive block copolymer structuring agents

Soft Matter ◽  
2019 ◽  
Vol 15 (40) ◽  
pp. 8077-8083 ◽  
Author(s):  
Jessica C. Tom ◽  
Christian Appel ◽  
Annette Andrieu-Brunsen
Keyword(s):  
Block Copolymer ◽  
Mesoporous Silica ◽  
Self Assembly ◽  
Stimuli Responsive ◽  
Silica Films ◽  
Functional Block ◽  
Evaporation Induced Self Assembly ◽  
Physical Entrapment

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.

TIME-RESOLVED IN SITU GISAXS EXPERIMENT OF EVAPORATION-INDUCED SELF-ASSEMBLY OF CTAB TEMPLATED SILICA THIN FILMS UNDER CONTROLLED HUMIDITY

2005 ◽  
Vol 04 (05n06) ◽  
pp. 873-878 ◽  
Author(s):  
S. DOURDAIN ◽  
M. COLAS ◽  
J. F. BARDEAU ◽  
O. GANG ◽  
B. OCKO ◽  
...  
Keyword(s):  
Thin Films ◽  
Self Assembly ◽  
Silica Matrix ◽  
Time Resolved ◽  
Silica Thin Films ◽  
Short Period ◽  
Cylindrical Micelles ◽  
Evaporation Induced Self Assembly ◽  
Morphologic Changes

The influence of controlled humidity on the phase transformation of CTAB templated silica thin films is studied by time-resolved in situ GISAXS measurements. It is shown that during a short period of time the silica matrix is flexible enough to follow the morphologic changes of the cylindrical micelles into spherical ones. During this time water can be uptaken and outtaken from the film. The evolution of the lattice parameters upon cycling dry and humid air is presented and discussed.

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