Design of Al-decorated C24N24 fullerene for efficient adsorption and removal of methylene blue dye from water

Abstract

In this study, density functional theory (DFT) is used to explore aluminum-doped porphyrin-like porous fullerene (Al₆@C₂₄N₂₄) as a potential adsorbent for scavenging aquatic carcinogenic methylene blue (MB) dye. The Al₆@C₂₄N₂₄ system demonstrates thermal stability up to 1000 K, implying the robust incorporation of Al atoms into the C₂₄N₂₄ framework. The adsorption analysis at the DFT-D3 level reveals that MB dye is efficiently adsorbed on the surface of the Al₆@C₂₄N₂₄ framework, with adsorption energies ranging from −2.03 to −2.97 eV. The charge-density-difference (CDD) mapping, partial-density of states (PDOS), and quantum theory of atoms-in-molecules (QTAIM) analyses validate the electrostatic interactions, facilitating MB chemisorption on the Al₆@C₂₄N₂₄ surface. The maximum uptake capacity assessment indicates that the Al₆@C₂₄N₂₄ system can effectively adsorb up to six MB molecules, highlighting its potential for efficient dye scavenging. Moreover, molecular dynamics (MD) simulations demonstrate the thermodynamically feasible formation of the 6MB-Al₆@C₂₄N₂₄ complex at 300 K in an aqueous environment, substantiating the existence of the complex in real scenarios. These findings provide a theoretical basis for experimental investigations, suggesting that Al₆@C₂₄N₂₄ could serve as an innovative wastewater purifier by scavenging organic carcinogenic dyes, contributing to advancements in environmental remediation technologies.