One-pot synthesis of NiFe2O4 integrated with EDTA-derived carbon dots for enhanced removal of tetracycline

Abstract

Recently, carbon-based nanomaterials especially carbon dots (CDs) show as the promising candidates for organic contaminant removal because of their abundant functional groups, easy-of-preparation and high surface area. However, the difficulties in separation and recycle of CDs arising from its high water solubility and low molecular weight limit its application in this area. Herein, we demonstrate a one-pot solvothermal method for fabricating NiFe2O4-carbon dot (NiFeC) nanocomposites, which solve its limitations and mitigate the usual fabrication drawbacks by self-assembly such as relatively weak interaction, time-consuming and lack of recycling potential. Series characterizations confirmed the successful fabrication of NiFeC nanocomposites with great uniformity in morphology and exhibited excellent dispersibility in water. The adsorption behavior of the as-prepared nanocomposites was systematically studied using kinetic and equilibrium experiments. Owing to abundant hydroxy and carboxyl groups introduced from CDs, NiFeC nanocomposites offered significantly enhanced tetracycline (TC) removal ability with the maximum adsorption capacity of 591.72mgg−1, as well as the excellent regenerability. Moreover, XPS and FT-IR analysis revealed the adsorption mechanism was attributed to surface complexation, cation exchange and electrostatic interaction between TC and the NiFeC. With the higher adsorption capacity and simpler synthesis method than traditional adsorbents, NiFeC nanocomposites have promising potential for the removal of TC from wastewater.