Carbon Aerogels: a study with different models of the effect resorcinol/catalyst at different ratios after pyrolysis and the effect on textural properties

Abstract

Eight samples of carbon aerogels were prepared at various resorcinol/catalytic (R/C) ratios (ranging from 25 to 1500) and followed the changes in structure after pyrolysis. Isotherms of N2 to 77 K were determined to calculate the textural parameters using Dubinin-Astakhov (DA), Barret Joyner and Halenda (BJH), Non-Local Density Functional Theory (NLDFT) and Quenched Solid Density Functional Theory (QSDFT) models. The results generated two series of samples. In series I, a single type of pores developed (microporous, at low R/C weight ratio). Series II developed mesoporosity to top gears of R/C (> 400). The specific areas ranged from 64 to 990 m 2 /g. Additional models were applied to the materials synthesized, which allowed for adjustment to a system of "cylinder-slit" pores by applying the QSDFT kernel, with an error percentage ranging from 0.03 to 0.74.

Thermodynamic study of adsorption of nickel ions onto carbon aerogels

“…For the study of all these models, the ASQiWin software is used. The detailed analysis of the results of the textural part have already been published in the literature by our research group [23, 24]. In summary, this interpretation concludes that the PSD (Pore Size Density) obtained from the adsorption of N 2 isotherms to 77 K using the kernel slot-cylinder pore modulation QSDFT (Quenched Solid Density Functional Theory) shows a micropore distribution in some cases monomodal and in other bi-modal.…”

“…Some formations of cavities in the surface of the materials are observed and as the R/C ratio increases, there is an increase in the roughness of the samples without modifying the interconnected structure. The formation of the bonds between the carbons makes the connections between their nodules are intense, preventing the rupture of the networks that are formed as the R/C ratio increases [24]. Similarly, a good combination of pore size distribution data (PSD) obtained from isotherms of N 2 adsorption and immersion calorimetry was observed, except for a pair of aerogels.…”

“…Similarly, a good combination of pore size distribution data (PSD) obtained from isotherms of N 2 adsorption and immersion calorimetry was observed, except for a pair of aerogels. Finally, the experimental and modeling results were critically discussed in the aforementioned publication [23, 24].…”

“…They were labeled as: carbon aerogels. Ae25, Ae50, Ae100, Ae200, Ae400, Ae600, Ae800 and Ae1500 [23, 24].…”