Novel CuO–SiO2 nanocomposites: synthesis, kinetics, recyclability, high stability and photocatalytic efficiency for Rose Bengal dye removal

A novel CuO–SiO2 nanoadsorbent, incorporating copper oxide (CuO) and silicon dioxide (SiO2), has been successfully synthesized using three distinct preparation processes: Mode-A (solution and solution), Mode-B (solution and nanoparticles), and Mode-C (nanoparticles and nanoparticles). The investigation focuses on evaluating the efficiency of the CuO–SiO2 nanoadsorbent, considering its synthesis process, reusability, and sustained performance over time, particularly in the removal of Rose Bengal dye. Characterization results revealed the formation of CuO–SiO2 nanocomposites structure irregular shapes morphology across all three-preparation processes. The average particle sizes for Mode-A, Mode-B, and Mode-C nanocomposites were determined as 18.1 nm, 15.6 nm, and 14.8 nm, respectively. Furthermore, the band gap energies of the CuO–SiO2 nanocomposites were measured at 2.2 eV, 1.8 eV, and 3.29 eV for Mode-A, Mode-B, and Mode-C, respectively. Remarkably, the CuO–SiO2 nanocomposite prepared using Mode-B demonstrated superior photocatalytic activity in degrading the anionic dye Rose Bengal, achieving a degradation coefficient of 84.8