Zeolite-templated carbons

Normally, carbon materials are characterised using the DFT which assumes a slit-like pore geometry [12]. However, these zeolite templated carbons are best described by the DFT-Hybrid... 

Yang Z, Xia Y, Sun X and Mokaya R (2006), Preparation and hydrogen storage properties of zeolite-templated carbon materials nanocast via chemical vapor deposition effect of the zeolite template and nitrogen doping , J Phys Chem B, 110, 18424. 

In order to improve the structural ordering of zeolite-templated carbons, Ma et al. have investigated systematically the synthesis of microporous carbons using zeolite Y as hard template. They used a two-step method to prepare an ordered, microporous carbon with high surface area, which retained the structural regularity of zeolite Y by filling as much carbon precursor as possible into the zeolite pores so as to prevent any subsequent partial collapse of the resulting carbon framework. In the... 

Gu, W., and G. Yushin. 2014. Review of nanostructured carbon materials for electrochemical capacitor applications Advantages and limitations of activated carbon, carbide-derived carbon, zeolite-templated carbon, carbon aerogels, carbon nanotubes, onion-Uke carbon, and graphene. Wiley Interdisciplinary Reviews Energy and Environment 3 424-473. 

Barata-Rodrigues et al. [73] reported that the CVD technique does not help improve the structural regularity of a zeolite-templated carbon. We indeed found that, when wet impregnation is followed by a CVD treatment, the XRD peak at 6° 20 can be observed, indicating the appearance of an ordered pore structure [75]. However, this XRD peak cannot be resolved for the carbon prepared without using the CVD technique [74]. An alternative route to the synthesis of ordered microporous carbons by using zeolite Y as template has also been described [88]. In addition, the use of other zeolite templates such as EMC-2 to improve structural regularity of replicated microporous carbons has been demonstrated... 

Nishihara H, Yang Q-H, Hou P-X, Unno M, Yamauchi S, Saito R, Paredes JI, Martmez-Alonso A, Tascon JMD, Sato Y (2009) A possible buckybowl-like structure of zeolite templated carbon. Carbon 47 1220-1230... 

Zeolite templated carbons exhibit high performance without extensive activation due to the high surface areas and long range orders of their porous structures. Wang et al. [37] used zeolite X (670 m. gr, 1.4 nm pore size) and 8 hr of chemical vapor deposition (CVD) to introduce carbon into the template. The resulting template CNX-2 (2700 m2.g i) had capacitance of 158 Rgy (at 0.25 A.gyi) and energy density of 25 Wh.gyi, respectively, in aqueous electrolyte. Due to the ordered nature of the pore structure, over 97% of the capacitance was retained at rates of 2 A.gyi. The zeolite could produce dense carbon pore structure (1.07 cm. g-i) and improved volumetric capacitance versus most activated carbon materials [37]. 

Portet, C. et al Electrical double-layer capacitance of zeolite-templated carbon in organic electrolyte. Journal of the Electrochemical Society 156, A1-A6, 2009. 

Nishihara, H. et al. A possible buckybowl-like structure of zeolite templated carbon. Carbon 47, 1220-1230, 2009. 

Microporous carbons have been prepared as inverse replicas of zeolites. " Zeolite-templated carbons (ZTCs) are prepared by filling the micropores of zeolites, snch as zeolite Y and X13, with a suitable carbon source, for example, furfuryl alcohol, followed by carbonization of composites and dissolution of the siliceous framework. As a result of the well-defined three-dimensional (3D) crystal structure of most starting zeolite materials, ZTCs exhibit amorphous carbon walls having a periodic arrangement of micropores. The ZTCs exhibit the same periodicity as the starting microporous templates in the range of 1.0-2.0 nm, as shown in Figure... 

Among the inorganic templates, zeolite produces more regulated pores as compared to the silica template. If nano-channels in zeolite are completely filled with carbonaceous precursor and then the carbon materials are extracted from the zeolite framework, one can obtain the porous carbon of which structure reflects the porosity of the original zeolite template. The ordered mesoporous silica templates, e.g., MCM-4 838,39,47 and SBA-1547 have been employed to prepare the ordered porous carbons by the procedures involving the pore filling of the silica template with carbonaceous precursor followed by carbonization and silica dissolution. The resulting pore sizes of the ordered mesoporous carbons are smaller than about 10 nm. 

FIGURE 3.15 Scheme of the template carbonization using zeolite Y. 

FIGURE 3.25 Diffusion of electrolyte ions into the pores of a conventional activated carbon and the ordered microporous carbon prepared using the zeolite template. 

Ania, C.O., Khomenko, V., Raymundo-Pinero, E., Parra, J.B., and Beguin, F. The large electrochemical performance of microporous doped carbon obtained by using a zeolite template. Adv. Fund. Mat. 17, 2007 1828-1836. 

As mentioned in the previous section, hollow zeolite spheres of LTA, FAU, BEA, MFI can be prepared in the presence of polystyrene beads as templates by using an LBL self-assembly technique. Recently, several research groups have tried to adopt similar methods to synthesize zeolite-template composites on the surfaces of templates with various shapes and sizes, properties, and structures through self-assembly or in situ-crystallization approaches. Subsequent removal of the templates forms zeolite materials with analogical skeletons of the templates. Up to now, the reported templates include microspheres, carbon fibers, polyurethane foams, and microbe structures,[144,145] as well... 

J. Rodriguez-Mirasol, T. Cordero, L.R. Radovic, and J.J. Rodriguez, Structural and Textural Properties of Pyrolytic Carbon Formed within a Microporous Zeolite Template. Chem. Mater., 1998, 10, 550-558. 

Paredes, J.I., Martinez-Alonso, A., Yamazaki, T., et al. (2005). Structural investigation of zeolite-templated, ordered microporous carbon by scanning tunneling microscopy and Raman spectroscopy. Langmuir, 21, 8817-23. 

Rodriguez-Mirasol, J., Cordero, T., Radovic, L.R., and Rodriguez, J.J. (1998). Structural and textural properties of pyrolytic carbon formed within a microporous zeolite template. Chem. Mater., 10, 550-8. 

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