Porous-CdS/Cu2O/graphitic-C3N4 dual p-n junctions as highly efficient photo/catalysts for degrading ciprofloxacin and generating hydrogen using solar energy.

• A simple method for synthesizing pCdS/Cu 2 O/g-C 3 N 4 composites is presented. • This work provides a new insight into the catalyst design. • Ciprofloxacin degradation reaction was over 18 times faster than pure g-C 3 N 4. • Hydrogen generation was over 18.4 times higher than pure g-C 3 N 4. • Hydrogen generation was comparable with recent publications in leading journals. We develop facile hydrothermal and precipitation approaches to fabricate porous CdS (pCdS) nanoparticles on octahedral Cu 2 O (1 1 1) microcrystals on C 3 N 4 and thus enabling to build novel pCdS/Cu 2 O/g-C 3 N 4 dual p-n Junctions. This dual p-n Junction structure would enhance charge carrier separation and transfer ability for achieving highly efficient photo/catalysis, which is much better than individual g-C 3 N 4 or pCdS/Cu 2 O p-n junctions. The degradation of ciprofloxacin (CIP) using pCdS/Cu 2 O/g-C 3 N 4 composites as a catalyst will make the reaction remarkably faster (over 18 times) than pure g-C 3 N 4. Its photocatalytic effect is well demonstrated through water splitting under simulated sunlight irradiation, where the hydrogen generation rate of 1.84 mmol h−1 g−1, i.e. over 18.40 times higher than pure g-C 3 N 4 , is achieved benefiting from its higher charge separation rate. This work provides not only a new insight into the catalyst design but also offer a stable and reusable pCdS/Cu 2 O/g-C 3 N 4 dual p-n Junctions composite as a highly efficient catalyst for use in environmental rumination and hydrogen generation. The comparison of the photocatalytic hydrogen production performance of the presented photocatalyst with some recent papers published especially in leading journals in this field proves further its significant advancement in this field. [ABSTRACT FROM AUTHOR]