Functionalized carbon materials

The high, partly superior performance of the biocarbon hybrids is worth underlining, as it is still the standard opinion that making processes more sustainable usually comes with a compromise in performance. This is clearly not the case for functional carbon materials and hybrids, which in our opinion is due to the fact that the more technological process of charring is replaced by a better controllable chemical process in a solvent, namely very hot water. 

Paraknowitsch JP, Thomas A (2012) Functional carbon materials from ionic liquid precursors. Macromol Chem Phys 213 1132-1145... 

Deuterium labeling of certain positions in the steroid nucleus can be a serious problem if suitably functionalized starting materials are not available or if a particular part of the molecule to be labeled is unsuitable for the various reactions described previously in this chapter. In these cases, the only practical solution to this problem is to incorporate the appropriately labeled carbon fragment by synthesis of the desired skeleton. 

Chemical vapor deposition (CVD) of carbon from propane is the main reaction in the fabrication of the C/C composites [1,2] and the C-SiC functionally graded material [3,4,5]. The carbon deposition rate from propane is high compared with those from other aliphatic hydrocarbons [4]. Propane is rapidly decomposed in the gas phase and various hydrocarbons are formed independently of the film growth in the CVD reactor. The propane concentration distribution is determined by the gas-phase kinetics. The gas-phase reaction model, in addition to the film growth reaction model, is required for the numerical simulation of the CVD reactor for designing and controlling purposes. Therefore, a compact gas-phase reaction model is preferred. The authors proposed the procedure to reduce an elementary reaction model consisting of hundreds of reactions to a compact model objectively [6]. In this study, the procedure is applied to propane pyrolysis for carbon CVD and a compact gas-phase reaction model is built by the proposed procedure and the kinetic parameters are determined from the experimental results. 

In this paper, we presented new information, which should help in optimising disordered carbon materials for anodes of lithium-ion batteries. We clearly proved that the irreversible capacity is essentially due to the presence of active sites at the surface of carbon, which cause the electrolyte decomposition. A perfect linear relationship was shown between the irreversible capacity and the active surface area, i.e. the area corresponding to the sites located at the edge planes. It definitely proves that the BET specific surface area, which represents the surface area of the basal planes, is not a relevant parameter to explain the irreversible capacity, even if some papers showed some correlation with this parameter for rather low BET surface area carbons. The electrolyte may be decomposed by surface functional groups or by dangling bonds. Coating by a thin layer of pyrolytic carbon allows these sites to be efficiently blocked, without reducing the value of reversible capacity. 

Kong, J., Chapline, M.G. and Dai, H., Functionalized carbon nanotubes for molecular hydrogen sensors, Advanced Materials, 13(18), 1384, 2001. 

Simultaneous to the understanding of some basics of hydrothermal carbonization using pure carbohydrate models, the synthesis of hydrothermal carbon materials using raw biomass was continued. It has been analyzed whether complex biomass - hy-drothermally carbonized - can also be directed to complex structural motifs with distinct surface polarities. Ideally, for this purpose one can use the structures and functionalization components already included in the biomass. We specifically selected waste biomass for material synthesis, starting products which are known to be hard to use otherwise, rich in ternary components, and applied different HTC conditions [29]. That way, one can avoid the food-raw materials competition, a prerequisite we regard as crucial for the development of a fully sustainable chemistry. 

Contrarily to the basal plane, the prismatic edges terminating the graphene layers as well as defects in the basal plane are highly reactive and usually saturated, with H, 0, or N atoms being the key players in most of the catalytic applications of carbon materials (see Chapter 19). The abundance of groups illustrated in Fig. 15.5 is well known from organic chemistry. These functionalities define the acidity/basicity and also the hydrophilic character of the nanocarbons. 

Inagaki, M., Carbon coating for enhancing the functionalities of materials. Carbon 2012, 50 3247-3266. 

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