Synergistic staggered heterojunction and surface plasmon resonance in P-doped Fe3O4/Zn3V2O7(OH)2.2H2O/Ag for enhanced photocatalytic degradation of ketoprofen.

Ketoprofen, a widely used non-steroidal anti-inflammatory drug (NSAID), is frequently detected as a persistent pollutant in aquatic environments. In this study, a ternary photocatalyst comprising microsphere P-doped Fe3O4, Zn3V2O7(OH)2.2H2O nanosheets, and Ag nanoparticles (pFZAg) was strategically synthesized to exploit the synergistic effects of type II heterojunction (staggered type) formation and surface plasmon resonance (SPR) for photocatalytic ketoprofen degradation. Among the investigated photocatalysts (pFe, ZnV, pFZ, and pFZAg), pFZAg demonstrated the highest photocatalytic activity toward ketoprofen degradation, achieving complete mineralization within 60 min, achieving TOC removal efficiency of 92.03 % under solar light irradiation (kobs = 0.055 min-1). pFZAg photocatalyst exhibits excellent recyclability for five consecutive cycles in DI water (87.8 %) and river water (76.9 %), proving its robustness and steady photocatalytic activity. Mechanistic investigations revealed that the efficient generation of •OH, O2•-, and 1O2 radicals played a pivotal role in the oxidative degradation pathway as studied by EPR and GC-MS analysis. Most importantly, the toxicity significantly reduced as verified by increasing density of algae in post-degraded ketoprofen solution. This work highlights the potential of engineered ternary heterojunction photocatalysts for environmental remediation, particularly for the degradation of persistent pharmaceutical contaminants in aquatic systems.