Visible-light-driven super-active Sn and GO single- and Sn/Cu Co-doped nanophotocatalysts for phenol degradation: Thin-film printability, thermal stability, and cytotoxicity assay

Sn- and graphene oxide (GO) single-doped and Sn/Cu co-doped titanium dioxide (TiO₂) nanoparticles were synthesized as printed-layer nano-photocatalysts for degradation of phenol under visible-light. The doped TiO₂ nanoparticles (Sn-doped-TiO₂, Cu/Sn-doped-TiO₂, and GO-doped-TiO₂) were synthesized via sol–gel method and calcinated at a temperature of 450 °C. X-ray diffraction (XRD), UV–Visible DRS analysis, Raman analyses, and Energy-dispersive X-ray spectroscopy (EDXS) were utilized to evaluate the crystalline structure and photocatalytic activities of doped-TiO₂ nanoparticles. Different screen-printing pastes were separately formulated with 26% w/w doped-TiO₂ nanoparticles (Paste1-to-Paste3) for printing onto microscope glass slides. Photocatalytic printed film was sustainable filter for unused suspension of nanoparticles in wastewater. The printed pasts were sintered at varying temperatures (100–500 °C), then three-layer printed nanoparticles sintered at 500 °C examined for photocatalysis. Photocatalytic activity of single-layer-printed GO-doped-TiO₂ nanoparticles was extraordinary (80% degradation of 10 ppm phenol solution). Hydroquinone, catechol, benzoquinone and acetic acid were observed to be produced at different concentrations over different time intervals as a result of phenol degradation for single-layer-printed GO-doped-TiO₂ nanoparticles sintered at 500 °C. Bandgap of GO-doped-TiO₂ nanoparticles was 2 eV, meaningfully lower than anatase TiO₂ (3.2 eV). The cytotoxicity assay applied for normal and cancer cells demonstrated cytocompatibility besides photodegradability. This novel process is a targeted, clean, cost-effective and on-demand approach, taking a big step toward decontamination of the environmental pollution.