Computational characterization of Ordered Mesoporous Carbon Adsorbent (CMK-3

V. CORNETTE; J.C.A DE OLIVEIRA; K. SAPAG; R.H. LÓPEZ

Granada

Simposio; 10th International Symposium on the Characterization of Porous Solids (COPS-X),; 2014

Porous carbons, owing to their surface properties and stability, are very attractive for applications in various areas, such as adsorption, purification of water, catalysis, electrochemistry, and others. Recently, the successful synthesis of mesostructured mesoporous carbons (MMCs) was discovered1 in which ordered mesoporous silicas were employed as templates. Ryoo and co-workers synthesized an ordered mesoporous carbon named CMK-3, which consists of two-dimensional (2D) hexagonal arrays of carbon nanorods. Compared to materials with disordered pore systems, MMCs allow precise control over their pore dimensions and arrangement, which is vital for applications requiring size and shape selectivity, hierarchical material organization, and pore accessibility. The development and availability of advanced molecular model has led to major improvements in the characterization of porous materials. The most of theoretical and simulation approach have considered simple geometries (like slit or cylindrical pore) to consider the pore shape which are typical model pores in activated microporous and mesoporous carbons. 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. Based on CMK-3 carbons synthesized by Ryoo et al., we present a detailed study by different molecular methods of this materials. Focused on getting the pore size distributions, which permit to obtain a better characterization of the porous material, we compare different geometrical models starting on basic cylindrical pore model followed by a mixed model (cylindrical and slit geometries) which are analyzed by different molecular theories such as the NLDFT, QSDFT and GCMC simulations. Finally a more detailed molecular model, considering specifically the real morphology of CMK3 pore, is studied by GCMC. The results obtained are compared with data collected from the TEM image