Synthesis and Photocatalytic Activity of Fe3O4–WO3–CQD Multifunctional System

Abstract

In this work, superparamagnetic Fe3O4 nanocrystalline was prepared by using citric acid as an additive and co-precipitation method. The Fe3O4–WO3–carbon quantum dot (CQD) metal oxide porous structure was constructed, characterized and analyzed. When the amount of citric acid added was 22.7 wt%, the specific saturation magnetization of Fe3O4 nanocrystals was 52.567 emu/g, and the Fe3O4–WO3 composite structure was agglomerated into spheroids having a diameter of about 200 nm. The constructed Fe3O4–WO3–CQD metal oxide porous structure has a specific surface area of 166.78 m2/g. In the experiment of adsorption and degradation of rhodamine B solution (20 mg/L), the decolorization rate of the dye by Fe3O4–WO3–CQD system was 54.42% after 60 min of dark treatment. After 240 min of photocatalysis, the dye decolorization rate increased by 14.17% to 65.56%. This shows that the photocatalytic performance of the sample was improved after the compounding process. The results provided that Fe3O4–WO3–CQD composite structure has great application potential in the field of photo-catalytic degradation of organic pollutants.