Tricomponent Coassembly Approach To Synthesize Ordered Mesoporous Carbon/Silica Nanocomposites and Their Derivative Mesoporous Silicas with Dual Porosities

2014 ◽  
Vol 26 (7) ◽  
pp. 2438-2444 ◽  
Author(s):  
Yuhui Li ◽  
Jing Wei ◽  
Wei Luo ◽  
Chun Wang ◽  
Wei Li ◽  
...  
2007 ◽  
Vol 121-123 ◽  
pp. 69-73
Author(s):  
Wei Hua Shen ◽  
Jian Lin Shi ◽  
Yu Fang Zhu

High ordered mesoporous carbon molecular sieves designated as CMK-3 and CMK-5 was synthesized using mesoporous silica SBA-15 as hard template, pre-polymerized furfuryl alcohol as a carbon souse by one-step impregnation. The effect of the furfuryl alcohol to silicas ratio have been investigated. XRD pattern, N2 sorption, FE-SEM, TEM, TG-DSC was used to characterize the property of the product. These results show that the CMK-3 and CMK-5 type mesoporous carbon can be controlled and facilely obtained.


NANO ◽  
2015 ◽  
Vol 10 (08) ◽  
pp. 1550110 ◽  
Author(s):  
Yanyan Ren ◽  
Le Yang ◽  
Liuding Wang ◽  
Hui Xing ◽  
Hongjing Wu

Low-density Fe-doped ordered mesoporous carbon (CMK-3)-silica (SBA-15) nanocomposites with different Fe contents have been prepared by a catalytic carbonization procedure followed by high-temperature calcination in N2. From field emission-scanning electron microscope (FE-SEM) and high resolution-transmission electron microscope (HR-TEM) images, it can be concluded that CMK-3 particles are dispersed homogeneously into a silica matrix and form a novel, special and interesting composite nanostructure. The metal species ([Formula: see text]18[Formula: see text]nm) are dispersed on the surface of frameworks during the catalytic carbonization procedure and endow a magnetic property to the carbon–silica nanocomposites. The optimal reflection loss (RL) calculated from the measured permittivity and permeability is [Formula: see text]19[Formula: see text]dB at 17.2[Formula: see text]GHz for an absorber thickness of 2.00[Formula: see text]mm. Moreover, the electromagnetic (EM) wave absorption less than [Formula: see text]10[Formula: see text]dB is found to exceed 5.76[Formula: see text]GHz as the layer thickness is 2.37 mm. The permittivity dispersion behaviors have been explained based on the Cole–Cole model and the conductivity contribution model. A new simple empirical model was also supposed to find the fitted curves of the multi-resonance imaginary permeability spectra of the composites. The EM wave can hardly be reflected on the absorber surface because of a better match between dielectric loss and magnetic loss, which originates from the combination of dielectric carbon–silica and magnetic Fe species.


Sign in / Sign up

Export Citation Format

Share Document