Fingerprints of heterogeneities from carbon oxidative process: A reactive molecular dynamics study

Abstract

Carbons are versatile, nanoporous materials useful in adsorptive separation and catalysis. The lack of long-range order, as revealed by neutron and x-ray diffraction and partial visualization of structural elements by microscopy techniques, makes the structural assessment of porosity extremely limited. This makes modeling and simulation an exceptionally challenging task. Here, we use reactive potentials and a graphene-based model to study the carbon morphology from the oxidative process and related gas–surface interactions. We obtained new heterogeneous models from the basal plane etching that presented improved performance compared to implicit (DFT-density function theory) and explicit models in the reproduction of reference experimental adsorption isotherms and heat from different carbons. We also generated a validated edge cross-linked configuration, able to reproduce adsorptive data in carbons with areas of 114 and 3700 m 2 /g. The cross-linked configuration is related to the disorder domains previously predicted in conceptual models. Those structures can be obtained by a procedure that combines gasification–reconstruction steps with high reproducibility, offering in-deep structural insights and opening up new opportunities for structure–property investigation. • New carbon heterogeneous model are obtained by reactive molecular dynamics. • Oxidative etching was mimic in the reactive modeling. • The new models presented improved performance. • The models reproduced adsorptive data from different carbons.