Eco-friendly synthesis of cadmium-loaded CaCO₃/PMMA nanocomposite for an enhanced photocatalytic activity for removal of organic dyes in the aqueous solution

The cadmium-loaded CaCO₃/PMMA nanocomposites were prepared from a natural carbonate source (dolomite, CaMg(CO₃)₂) using biomimetic method. The XRD results showed that the synthesized product has exhibited a crystalline and rhombohedral structure with a size range of 30–40 nm. The absorption and emission values of CPCD₆ (CaCO₃/PMMA: Cd (0.12 M)) nanoparticles are red-shifted, and the band gap values depict blue-shifted (2.8 eV). The HR-TEM analysis of the sample indicates that the products have aggregated with spherical-like structures. The TG-DTA analysis revealed good thermal stability approximately at 830 °C. The photocatalytic analysis was performed on the CPCD₆ nanocomposite to remove methylene blue (MB) and methyl orange (MO) dyes from an aqueous solution under UV-visible light. The results show that the photocatalyst (CPCD₆) exhibits high degradation efficiency for methylene blue (MB) (93%) when compared with methyl orange (MO) (89%) dyes. To evaluate the effectiveness of the product, several scavengers (AA, AgNO₃, EDTA 2Na, and IPA) are employed. The CPCD₆ nanocomposites showed great potential for the removal of organic dyes from aqueous media.