Hollow carbon capsules

Various groups have reported promising EC electrode materials using hierarchical nanostructured carbons with well-organised pore structures, large specific surface areas and, particularly, an interconnected pore network. Portet et al. has reported 146 F g for zeolite-templated hollow-core mesoporous carbon s)mthesised by chemical vapor deposition (CVD) method [43]. Murali et al. has also reported hollow carbon capsules with specific capacitance of... 

J.H. Kim and J.-S. Yu, Erythrocyte-like hollow carbon capsules and their application in proton exchange membrane fuel cell, Phy. Chem. Chem. Pints. 12, 2010, 15301-15308. 

FIG. 13 TEM micrograph of a hollow composite nanoparticle/polymer capsule dried on a carbon grid. The hollow composite capsule was obtained after removal of the ME core from Si02/PDAD-MAC-coated ME particles by treatment with hydrochloric acid. The shadowing seen is a result of collapse and overlapping of the hollow capsule upon drying. (From Ref. 110.)... 

The Vitagen project using immortalized hepatic cells in a hollow fiber capsule in combination with a carbon-based toxin removal system is worthy of special note. The ELADTM bioartiflcial liver support system is designed to combine the unique... 

The sphere synthesis has been extended into other materials. For example, mesoporous carbon capsules[285] with hollow core and mesoporous shell structures were synthesized using submicrometer-sized solid core and mesoporous-shell silica spheres as templates. 

S.B. Yoon, K. Sohn, J.Y. Kim, C.H. Shin, J.S. Yu, and T. Hyeon, Fabrication of Carbon Capsules with Hollow Macroporous Core/Mesoporous Shell Structures, Adv. Mater., 2002, 14, 19-21. 

MANGANESE CARBONATE PARTICLES PREPARATION BY COLLOIDAL AGGREGATION FOR HOLLOW POLYELECTROLYTE CAPSULES FABRICATION... 

Method for synthesis of monodisperse spherical-like manganese carbonate (MnCOs) particles by colloidal aggregation process is developed. Hollow polyelectrolyte capsules have been prepared by means of layer-by-layer absorption of charged polyelectrolytes on microsized MnCOs particles with the subsequent decomposition of a micrometer nucleus. The use of inorganic templates is a way for clean capsules fabrication. The manganese carbonate particles and capsules obtained were investigated by SEM, SFM, XRD, and confocal fluorescent microscopy. 

Figure 2. Confocal microscopy and SEM images of hollow polyelectrolyte capsules prepared by layer-by-layer on manganese carbonate particles. Scalebar is 5 pm. 

Bhattacharjya, D., M. S. Kim, T. S. Bae, and J. S. Yu. 2013. High performance supercapacitor prepared from hollow mesoporous carbon capsules with hierarchical nanoarchitecture. Journal of Power Sources 244 799-805. 

FIGURE 2.48 FESEM images of (a) hollow carbon spheres with open windows, (b) hollow carbon spheres without open windows, (c) walnntlike carbon hollow spheres, and (d) carbon capsules. (From Zhou, Z., Yan, Q., Su, R, and Zhao, X.S. JMater Chem 15 2569-2574, 2005. With permission.)... 

Takashi Sasaki, Kttagawa Takayki, Sato Shinataro et al. Core/ shell and hollow polymeric capsules prepared from calcium carbonate whisker. Polvmer Toum/il 37(6) 434-438, 2005. 

Antipov AA, Shchukin D, Fedutik Y, Petrov AI, Sukhonikov GB, Mohwald H (2003) Carbonate microparticles for hollow polyelectrolyte capsules fabrication. Colloids Surf A 224 175-183... 

J.-H. Kim, B.-Z. Fang, S.-B. Yoon and J.-S. Yu, Hollow core/mesoporous shell carbon capsule as an unique cathode catalyst support in direct methanol fuel cell, Appl. Catal, B 88,2009, 368-375. 

Monodisperse manganese carbonate particles with average size of 3.7 pm were used. We used the self-assembly method to prepare (PSS/PAH)4 hollow capsules. 

It should also be noted that many of the previously reported latex 1-b-l modifications have described the deposition of layers of redox enzymes [55, 84, 85], and hence these structures could also be used as labels. Hollow capsules have also been used to entrap enzymes [101]. While enzyme stability can sometimes be an issue, the sensitivity provided by enzymes is often very good. For example, 1-b-l deposition of alkaline phosphatase onto carbon nanotubes resulted in electrochemical DNA sensing down to 5.4 aM [132]. In comparison with a nanotube, a latex sphere of diameter 0.5 m presents a very much larger surface area for immobilization. Finally, virtually everything stated in this chapter regarding DNA labeling can equally be applied to the labeling of antibodies. 

A. Antipov, D. Shchukin, Y. Fedutik, A. I. Petrov, G. B. Sukhorukov and H. Moehwald, Carbonate microparticles for hollow poly electrolyte capsules fabrication. Colloids and Surfaces, A Physicochemical and Engineering Aspects, 224,175-184 (2003). 

Different colloidal cores can be decomposed after multilayers are assembled on their surface. If the products of core decomposition are small enough to expel out of polyelectrolyte multilayer the process of core dissolution leads to formation of hollow polyelectrolytes shells (Fig. 2.1, d-f). Up to now, various colloidal templates such as organic and inorganic cores, like MF-particles, organic crystals, carbonate particles and biological cells were used as templates for hollow capsule fabrication. Decomposition can be done by different means, such as low pH for MF- and carbonate particles [43], organic water miscible solvents for organic crystals [44] and... 

FIGURE 12.6 (a) Illustration of the preparation of mesoporous Au-mesoporous carbon and silica capsules using glucose as carbon source. (From Kim, J. Y. et al., Chemical Communications, 790, 2003.) (b) TEM images of Au nanoparticles in microporous carbon hollow spheres prepared from dopamine as the carbon precursor. The carbon spheres were as large as the Au-silica template spheres, approximately 400 nm in diameter, and the carbon walls were A nm thick. (From Liu, R. et al., Angewandte Chemie-Intemational Edition, 50, 6799, 2011.)... 

F measured using different ionic liquids [44]. Similar hollow mesoporous carbon (HMC) capsules derived from thioether-derived bridged organosilica were also reported with specific capacitance of 121 F g"i [45]. 

M.-S. Kim, S.-B. Yoon, K.-N. Sohn, J.-Y. Kim, G.-H. Shin, T.-H. Hyeon and J.-S. Yu, Synthesis and characterization of spherical carbon and polymer capsules with hollow macroporous core and mesoporous shell structures, Microporous Mesoporous Mater. 63, 2003,1-9. 

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