Removal of Cu and Co ions form polluted water via Bi-TiO2 loaded on g-C3N4 nanostructures

This study surveys the impact of Bi@TiO₂ on the separate and combined adsorption of Cu (II) and Co (II) heavy metals in a water-based solution using g-C₃N₄ nanosheets. The Bi@TiO₂@CN nanostructures are effectively produced using the sol–gel technique and ultrasound method. The manufactured materials of Bi@TiO₂@CN are confirmed by SEM, EDX, XRD, FTIR, and XPS characterizations. The BET surface area was 45.43 m²/g, and the pore size distribution is 1.5406 nm. Nanostructures exhibit significant adsorption capabilities for Cu (II) (562.7 mg/g) and Co (II) (547 mg/g) after 24 h under optimum experimental conditions. The adsorption isotherm models have a strong agreement with the Langmuir isotherm, while the investigation on kinetics model fitting demonstrates an excellent fit with the pseudo-second-order. Furthermore, the adsorbent composite was regenerated in four cycles without loss of efficiency or stability. This study offers valuable insights into the significance of Bi@TiO₂@CN nanostructures in achieving extremely efficient, fast, and simultaneous removal of heavy metals.