Enabling dual-functionality material for effective anionic and cationic dye removal by using Nb2O5/MgAl-LDH nanocomposites

Abstract

The development of adsorbents capable of adsorbing both anionic and cationic dyes in wastewater treatment remains a challenge. This study presents the successful fabrication of Nb₂O₅-MgAl layered double hydroxide (LDH) nanocomposites for the effective removal of methylene blue (MB) and Congo red (CR) dyes via a one-step hydrothermal method. Incorporating a small amount of Nb into MgAl-LDH proved to be an effective strategy for creating nanocomposite materials with dual characteristics. The material’s morphological and crystalline structures were confirmed using FESEM-EDS and XRD. Incorporating Nb during the material preparation led to a remarkable enhancement in the material’s adsorption capacity - up to 3.4-fold and 9.0-fold increases for CR and MB, respectively. The kinetic and point zero charge analysis confirmed that the adsorption of the dyes onto the adsorbent surfaces occurred via an ionic interaction mechanism. These findings offer a promising alternative for fabricating dual-functional adsorbents, enhancing the effectiveness of dye removal in wastewater treatment technologies.