Fabrication of beta zeolite supported Ti3+-TiO2/CdS composite for ultrahigh-performance photodegradation of tetracycline under visible-light illumination

In this work, beta zeolite supported Ti3+-TiO2/CdS heterojunction was prepared for photodegradation of tetracycline under visible-light irradiation, and zeolite served as a support for the high dispersions of the Ti3+- TiO(2 n)anoparticles. The obtained zeolite/Ti3+-TiO2/CdS heterojunction showed a relatively high surface areas of approximately 63.2 m(2) g(-1), much higher than those of the prepared Ti3+-TiO2/CdS (27.1 m(2) g(-1)), Ti3+-TiO2 (36.5 m(2) g(-1)), and CdS (31.1 m(2) g(-1)), strongly demonstrating the significant of zeolite for high dispersion of the Ti3+-TiO2/CdS composite. Besides, the experimental results also showed that the photocatalytic degradation efficiency could reach 78 % in 3 min for the zeolite/Ti3+-TiO2/CdS heterojunction, and the corresponding rate constant was as high as 0.788 min (-1), which was 26.90 times that of pristine Ti3+-TiO2, 2.24 times of pristine CdS, and 2.04 times of the Ti3+-TiO2/CdS composite, mainly because of the supporting effects of zeolite and the formation of Ti3+-TiO2/CdS heterostructure for highly enhanced charge separation. In addition, the trapping experiment revealed that the main reactive species involved in tetracycline degradation were attributed to the photo-generated holes and ?O-2(-) species.

Automated summary

In this study, a beta zeolite supported Ti3+-TiO2/CdS heterojunction was prepared for the photodegradation of tetracycline under visible-light irradiation. The zeolite served as a support for the high dispersions of the Ti3+-TiO2/CdS composite, leading to a significant increase in the surface area. Experimental results showed that the zeolite/Ti3+-TiO2/CdS heterojunction exhibited a high photocatalytic degradation efficiency, mainly due to the supporting effects of zeolite and the formation of the Ti3+-TiO2/CdS heterostructure for enhanced charge separation.