Development of nanoporous carbon models with tunable pore structures via the random packing-virtual atom method

Abstract

Nanoporous carbon (NPC) is widely utilized due to its highly developed pore structure. The complex structure-property relationships of NPC necessitate simulation methods to complement experimental approaches, with structural model construction serving as the foundation. Regulating pore structures during construction of NPC models poses a significant challenge, and existing strategies for introducing pores have inherent limitations. In this work, NPC models were constructed using the random packing method, incorporating virtual atoms (VAs) to regulate pore development, achieving targeted control over the pore structure. The results indicate that the system density is a critical factor in determining the porosity range of NPC models, whereas VAs provide an effective means to regulate pore characteristics. By adjusting the number and radius of VAs, the pore characteristics of the models can be tuned, although their effects on different features vary. The number of VAs significantly influences SSA, which increases with the number of VAs, whereas VA radius predominantly affects porosity, increasing as the radius expands. Furthermore, the NPC-SDG-AC model was developed with an SSA of 968 m²/g and a pore size distribution consistent with actual microporous distribution. NPC-1, NPC-2, and NPC-3 models were also constructed, exhibiting mesoporous, large microporous, and small microporous characteristics.