A scalable fabrication of defective carbon nitride nanosheets for the high-efficiency photocatalytic removal of pollutants in water

Large scalable fabrication of high-performance photocatalysts is one of the most key points for developing advanced photocatalysts from ancient times to eternity. Here, polymeric carbon nitride nanosheets (CNS) was obtained by a facile way of calcining the precursor ultrasonically dispersed and uniformly spread on the inner wall of the crucible. By adding melamine and thiourea together as precursors, CNS has rich nitrogen defects. These abundant N defects in CNS (US-CNS−NV) alter the charge distribution on the catalyst surface, increase the dipole moment of material, reveal the enrichment of electrons at the nitrogen defects, and lead to HOMO and LUMO separation. Therefore, compared with pure PCN, US-CNS−NV shows 3.2 times for the photoreduction Cr(VI) and further improved 1.48 times in the co-existed organic pollutants of Rhodamine (RhB) environment. Besides, several different organic pollutants including RhB, Tetracycline (TC), Ciprofloxacin (CIP), and Ofloxacin (OFLX) were also investigated, and all results showed that US-CNS−NV displayed the highest degradation rate compared with PCN and CNS. Lastly, scale-up experiments with 100 cm × 40 cm × 2 cm have been conducted under ambient sunlight conditions, 10 ppm of RhB are approximately 100 % degradation with 30 min of continuous operation under sunlight. The present work provides a strategy to prepare high-performance carbon nitride photocatalysts containing N defects on a large scale.