Introduction: The growing environmental issues concerning synthetic dyes such as Fast Green FCF and Orange II Sodium Salt have motivated the search for effective photocatalytic materials for their destruction. Rare-earth metal oxides, particularly Ytterbium Oxide (Yb₂O₃), are gaining attention for their good electrical characteristics, thermal stability, and ability to reduce electron–hole recombination. This study produced and tested Yb₂O₃ nanoparticles for their photocatalytic performance under visible light irradiation. The spectrophotometric investigation showed significant degradation efficiencies, indicating Yb₂O₃ as a suitable nanocatalyst for dye remediation applications.

Methods: Yb₂O₃ nanoparticles were synthesized via co-precipitation and evaluated for photocatalytic activity in degrading synthetic dyes under visible light. UV-Vis spectroscopy, FTIR, XRD, and SEM-EDX were employed to confirm the structural, optical, and morphological properties of the generated Yb₂O₃ sample. The photocatalytic activity was investigated using two commonly used azo dyes, Fast Green FCF and Orange II Sodium Salt.

Results: The spectrophotometric evaluation of dye degradation revealed that the generated material has high photocatalytic efficacy. Yb₂O₃ nanoparticles degraded Fast Green FCF and Orange II Sodium Salt by 85% and 83%, respectively, after 105 minutes of visible light exposure.

Conclusion: This study emphasizes the efficiency of Yb₂O₃ nanoparticles as a visible light-responsive and stable photocatalyst for the degradation of persistent synthetic dyes. The findings highlight the potential of rare-earth-based nanomaterials in enhancing sustainable and eco-friendly wastewater treatment technologies, hence contributing to continuing environmental remediation efforts.