Synthesis of Fe3O4/Carbon Quantum Dots Hybrid for Efficient Removal of Congo Red Dye from Aqueous Solution

During the past decades, the release of toxic pollutants into aquatic environment has continuously increased due to rapid industrialization and civilization. The presence of organic dyes, such as Congo Red (CR), can be dangerous to both human and aquatic life. Therefore, their removal is an imperative need. Many technologies have been developed for water treatment. Among them, adsorption is the most popular due to its simplicity and low cost. Aim of this work is to synthesize an Fe3O4/carbon quantum dots (C-QDs) adsorbent and evaluate its performance in the removal of CR dye from aqueous solutions. More specifically, adsorbent Fe3O4/C-QDs was successfully synthesized via a solvothermal method, using ferrocene (C10H10Fe) and hydrogen peroxide (H2O2) as starting materials. The process took place in a Teflon-lined autoclave at 200 ℃ for 18 h in the presence of acetone. A series of Fe3O4/C-QDs hybrids were synthesized by adding different amounts of H2O2 aqueous solution, in order to investigate their physicochemical properties. The obtained Fe3O4/C-QDs hybrid materials were characterized using XRD, TEM, micro-Raman, FT-IR, and N2 adsorption/desorption measurements. Lastly, the adsorption capacity of the Fe3O4/C-QDs toward CR was investigated using a UV-Vis spectrophotometer.