Atomistic examination of carbon nanotube dispersion in Self-Sensing cementitious materials using surfactants

This study investigates the potential of various surfactants to improve the dispersion of carbonnanotubes (CNTs) within self-sensing cementitious materials. By enhancing the material's electricalconductivity, such dispersion can augment its sensing capabilities. The research focuses on overcoming theinherent challenge of CNT agglomeration arising from their strong Van der Waals attraction.While previous studies have explored surfactant-based dispersion primarily through techniques likeUV-vis analysis, this work delves deeper, utilizing molecular dynamics simulations and adsorption energyconcepts to unravel the atomistic interactions between four common surfactants and CNTs. The chosensurfactants – sodium dodecyl sulphate (SDS), sodium dodecyl benzene sulfonate (SDBS),cetyltrimethylammonium bromide (CTAB), and carboxymethyl cellulose (CMC) – represent diversechemical structures and functionalities.Analysis of adsorption energies reveals that CMC exhibits the highest dispersing potential due to itsstrong interaction with CNTs, whereas CTAB demonstrates the least potential. Furthermore, the adsorptionbehaviour of SDS, SDBS, and CTAB is characterized by tail-to-body interactions with the CNTs, involvingeither wrapping or flat-lying configurations.This atomistic-level understanding provides valuable insights into the dispersion mechanisms ofdifferent surfactants. Such knowledge can guide the development and selection of optimal surfactants forachieving effective CNT dispersion and maximizing the self-sensing performance of cementitiousmaterials.

کلیدواژه ها:

Carbon nano tube ، Self-sensing materials ، Molecular dynamics ، Dispersion