Evaluation of a mixed geometry model for the characterization of the Pore Structure of Ordered Nanoporous Carbons by Monte Carlo Simulation

V. YELPO; V. CORNETTE; D. BARRRERA; JHONNY V. ROCHA; R. H. LÓPEZ; K. SAPAG

Workshop; the 7th International Workshop "Characterization of Porous Materials: from Angstroms to Millimeters"; 2015

Energy and environmental problems have created the need of designing new materials that can be used in more efficient processes with high selectivity. Nanostructured carbon (NC) have attracted rapidly attention due to their physicochemical properties useful in many application as: separation processes (CH4/CO2 and N2/O2), gases storage (CH4 and H2), gases capture (CO2) and energy storage as electrodes in batteries and supercapacitors. The methods like NLDFT, QSDFT and Gran Canonical Monte Carlo simulation have been originally developed assuming simple geometry (slit-shaped, cylindrical, etc) [1,2]. However, the emergence of novel materials with pre-designed pore morphology (obtained by synthesis routes, which make use of structure directing agents or hard templates) requires the development of new methods, which take into account the morphological specifics of these structures. In this work a series of nanostructured carbons from CMK-3 to CMK-5 using SBA- 15 templates were characterized by Monte Carlo simulations. To this end, we have built a set of hybrid kernels called mixed geometry model (MGM) which comprising three set of isotherms (kernel) built based on slit, cylindrical and CMK-3 (hexagonally arranged four carbon rods constitute a simulation unit cell) pores in the Grand Canonical ensemble. The simulations results showed a good agreement with experimental adsorption isotherms. The PSD?s obtained by MGM allows to identify in a detailed way the contribution of each geometry in micro and meso-pores area. [1] G. Y. Gor, M. Thommes, K. a. Cychosz, and A. V. Neimark. Carbon 50 (2012) 1583?1590 [2] D. Barrera, M. Dávila, V. Cornette, J. C. A. de Oliveira, R. H. López, and K. Sapag, Microporous and Mesoporous Materials 180 (2013) 71?78.