Fabrication of Gd2O3-Loaded nitrogen-rich C3N5@PANI hybrid nanocomposites: Unlocking efficient photocatalysis for long-Term organic dye degradation in wastewater treatment

In this study, PANI@g-C₃N₅/Gd₂O₃ nanocomposites were made using a simple chemical process that combined PANI with the nitrogen-rich and potent chemical stability of g-C₃N₅ and Gd₂O₃. XRD, SEM-EDX, TEM, BET, UV-DRS, and PL investigations confirmed nanocomposites crystallographic, physicochemical, structural, and optical properties. PANI@g-C3N5/Gd₂O₃ exhibited exceptional photodegradation capabilities when subjected to toxic dyes, including erythrosine (Ey) and rhodamine (RhB). The g-C₃N₅/Gd₂O₃ nanocomposite was optimized for mass ratio with Gd₂O₃, and the addition of PANI further increased the specific surface area of the g-C₃N₅/Gd₂O₃ matrix. The prepared photocatalyst degraded RhB and EY almost completely within 75 and 60 min, respectively. The band gap energy of g-C₃N₅ decreased after adding Gd₂O₃ and PANI. The synergistic effects of g-C₃N₅, Gd₂O₃, and PANI reduced electron-hole charge carrier recombination at the photocatalyst interface, enhancing photocatalytic activity. Radical quenching studies showed that O₂^• and ^•OH were crucial to photocatalysis. After four cycles, the PANI@g-C₃N₅/Gd₂O₃ nanocomposites showed 93 % dye removal efficiency and excellent stability, suggesting environmental remediation potential.