Efficient photocatalytic degradation of sulfasalazine and reduction of hexavalent chromium over robust In₂S₃/Nd₂O₃ heterojunction under visible light

The design and synthesis of visible light driven heterojunction photocatalyst of a novel In₂S₃/xNd₂O₃ nanocomposites (where x = 5, 10 and 15 wt% Nd₂O₃) were constructed via simple two-step process, involving hydrothermal and ultrasonication. The prepared materials were characterized extensively to reveal information about their morphology, optical properties, phase composition, chemical states and electrochemical properties. Consequently, the efficient photocatalyst were studied double role photooxidation of sulfasalazine (SSZ) and photoreduction of Cr(VI) in environmental modal water pollutants under visible light illumination. The catalytic activity of In₂S₃/Nd₂O₃ nanocomposite was found to be dependent an optimal In₂S₃/10wt%Nd₂O₃ and dose, contact time and concentration of the pollutant. The maximum efficiency attainment of the Cr(VI) reduction was 95.23% and SSZ degradation was 96.19% within 35 and 80 min, respectively, which was multi-fold times greater than the efficiency of pristine In₂S₃ and Nd₂O₃. The enhanced efficiency pointed out the proper band alignment and intimate interfacial contact in the In₂S₃/10 wt% Nd₂O₃ p-n heterojunction, which facilitate the better charge separation and transfer between In₂S₃ and Nd₂O₃ photocatalyst. The photocatalyst have superior photostability and better recyclability, after the fifth run the activity was only reduced 4% for Cr(VI) and 7% for SSZ. Finally, a plausible band alignment and favourable charge transfer pathway for the generation oxidative species were proposed depends upon the scavenger study. This study reveals the versatile nature of In₂S₃/xNd₂O₃ heterojunction and its efficient photocatalysis of both emerging pharmaceutical contaminant and heavy metal in water.