Multifunctional Z-Scheme g-C3N4/SBA-15/Bi2Fe4O9 Nanocomposite for Simultaneous Photocatalytic Degradation of Organic Pollutants, Heavy Metal Ion Adsorption, and Thermo-Responsive Drug Delivery

Background: The simultaneous remediation of organic pollutants, heavy metals, and the need for smart drug delivery systems demand multifunctional nanomaterials. Integrated platforms addressing environmental and biomedical challenges are critical for sustainable nanotechnology. Methods: A novel Z-scheme g-C3N4/SBA-15/Bi2Fe4O9 nanocomposite was synthesized via sol-gel and surface functionalization techniques. Characterization included XRD, SEM, TEM, XPS, FTIR, UV-Vis DRS, and BET analysis. Response surface methodology (RSM) optimized synthesis and performance parameters. Results: The nanocomposite achieved 95% photocatalytic degradation of Congo Red in 120 min under visible light, adsorption capacities of 150, 135, and 120 mg/g for Pb(II), Cu(II), and Cd(II), respectively, and 80% doxorubicin (DOX) release at 45°C. Conclusion: This multifunctional nanocomposite offers a scalable solution for environmental remediation and targeted drug delivery, integrating Z-scheme photocatalysis, heavy metal adsorption, and thermo-responsive drug release.