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/xNd(2)O(3) nano-composites (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/xNd(2)O(3) heterojunction and its efficient photocatalysis of both emerging pharmaceutical contaminant and heavy metal in water.

Automated summary

In this study, a novel visible light driven heterojunction photocatalyst of In2S3/xNd(2)O(3) nano-composites was designed and synthesized via a simple two-step process. The prepared materials exhibited efficient photocatalytic activity for the double role photooxidation of sulfasalazine and photoreduction of Cr(VI) under visible light illumination. The enhanced efficiency was attributed to the proper band alignment and intimate interfacial contact in the In2S3/10 wt% Nd2O3 p-n heterojunction, which facilitated better charge separation and transfer. The photocatalyst also showed superior photostability and recyclability.