Multiple photocatalytic applications of non-precious Cu-loaded g-C3N4/ hydrogenated black TiO2 nanofiber heterostructure

TiO2 -based semiconductors are widely utilized for photocatalytic H(2 )evolution and environmental remediation; however, there are limited studies on a single photocatalyst that exhibits high photocatalytic performance in multiple applications. Herein, a non-precious Cu-loaded g-C3N4/1D hydrogenated black TiO2 nanofiber (CuCNBTNF) heterostructure was fabricated and investigated for H-2 evolution, gaseous organic pollutant removal, and aqueous dye pollutant removal under simulated solar or daylight fluorescent lamp irradiation. A CuCNBTNF sample with a CN-to-Cu/BTNF wt% of 5 (CuCNBTNF-5) showed the highest photocatalytic performance for H-2 evolution (16.9 mmol g(-1)), gaseous ethylbenzene removal (63.2%), and aqueous rhodamine B removal (86.2%). In addition, the photocatalytic performance of CuCNBTNF-5 was much higher than those of the selected reference catalysts, which was ascribed to the synergistic interaction of Cu, g-C3N4, and black TiO2 nanofiber. The enhanced charge carrier separation efficiency was inferred from the photoluminescence emission spectra. The H-2 evolution yield remained essentially constant after five cycles, indicating the long-term photostability of the photocatalyst. A type II heterojunction mechanism of CuCNBTNF for H-2 evolution and pollutant degradation was proposed on the basis of hydroxyl radical measurements and analysis of band energy structure. Therefore, the CuCNBTNF photocatalyst is a promising candidate for multiple photocatalytic applications.