Pyrolysis, organic aerogels

Carbon aerogels were first synthesized by Pekala in 1989 through pyrolysis of organic aerogels [28,29]. They display three-dimensional random close-packed monolithic structure [30,31] of slightly overlapping carbon spheres (3 to 30 nm)... 

An alternate method to make conductive aerogels is to employ a network that is inherently conductive, like carbon. Carbon aerogels can be prepared by pyrolysis of resorcinol—formaldehyde organic aerogels. The resultant aerogels have conductivities exceeding 25 S cm. ... 

Nanocomposited carbon aerogels represent a different approach because of the organic nature of the precursory gel and the pyrolysis step [11]. In this case, high metal content can be achieved (up to 46% in the case of Pd-doped carbon aerogel)... 

Thus, europium loaded gels were prepared. Some of them were dried by solvent evacuation at CO2 supercritical conditions to obtain the Eu-organic aerogeh After pyrolysis at 1050 °C a Eu-carbon aerogel was obtained (entries 2-4 of Table 5.7). The materials were tested as catalysts in Michael additions (Scheme 5.11). We performed the reaction of ethyl 2-oxocyclopentanecarboxylate and 3-buten-2-one... 

The BET surface area and pore structures of the RF and carbon aerogels with different R/C ratios and RF mass concentrations are shown in Table 36.3. The surface area of carbon aerogels increases dramatically after pyrolysis, which is due to the creation of micropores as a result of evaporative loss of organic moieties. It is also shown that the micropore area of carbon aerogels decreases with the increase in density [60]. 

Carbon aerogel Aerogel obtained by pyrolysis of an organic (polymeric) aerogel under protective atmosphere... 

Preparation of the Aerogel Composites. A new approach free of these problems, is to generate carbonaceous structures in silica aerogels either by pyrolysis of organically modified aerogels (Scheme 2) or by pyrolysis of gaseous organic compounds... 

Optimization of the pyrolysis process of organically substituted silica aerogels RxSiOi-O 5x showed the following trends (6). Numerical values for some examples are given In Table I. 

Pyrolysis of CH4 is obviously facilitated by the presence of carbon nuclei. We wanted to test whether the very active surface of silica aerogels alone is sufficient to generate carbonaceous structures from methane. When a carbon-free silica aerogel (i.e. an aerogel not substituted by organic groups) was heated to 1000°C and then... 

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