Biobased Tricomponent (carboxymethyl chitosan/ cerium dioxide/iron III oxide) nanocomposite flakes for multifarious environmental decontaminations: magnetically separable and antimicrobial photocatalyst

Carboxymethyl chitosan (CMCs) has been widely used in wastewater treatment due to its efficient functional groups. To boost its efficacy, a nanocomposite with two metal oxides, cerium dioxide (CeO ₂ ) and iron oxide (Fe ₂ O ₃ ), was formed using the ball milling technique. Two concentrations (0.15 and 0.3g) of both metal oxides were loaded to CMCs and labeled as 0.15CeO ₂ /Fe ₂ O ₃ /CMCs and 0.3CeO ₂ /Fe ₂ O ₃ /CMCs nanocomposite and their photocatalytic performance was compared with the blank CMCs. Upon grinding, CMCs exhibited flake-like shapes that were significantly coated with CeO ₂ and Fe ₂ O ₃ . The nanocomposites were evaluated for their photocatalytic performance by measuring the degradation of Malachite Green (MG) dye under various conditions. The 0.15CeO ₂ /Fe ₂ O ₃ /CMCs nanocomposite successfully achieved complete dye degradation at a concentration of 15 mg/L after 150 min, while the 0.3CeO ₂ /Fe ₂ O ₃ /CMCs seized the degradation in 120 min. The research found that 400 ppm of catalyst was the ideal catalyst dose and that a pH 6 was optimum for photocatalytic degradation. The antibacterial activity was assessed against Gram-positive and negative bacteria and the 0.3CeO ₂ /Fe ₂ O ₃ /CMCs exhibited notable antibacterial efficacy. The overall results reveal that CeO ₂ /Fe ₂ O ₃ /CMCs nanocomposite flakes are efficient for the photocatalytic breakdown of organic dyes in wastewater emphasizing their potential for addressing environmental issues and combating microbial contamination.