In-situ construction of dual Z-scheme TiO2/CuBi2O4/Bi2O2CO3 heterojunction for exceptional visible-light photocatalytic tetracycline removal

Rational development of innovative photocatalysts with efficient interfacial separation and stronger oxidation–reduction ability of photo-generated carrier is critical for environmental antibiotic purification. In this work, a novel dual Z-scheme heterojunction nanocomposites were fabricated based on the in-situ growth of CuBi 2 O 4 nanoparticles onto the surface of TiO 2 nanorods and Bi 2 O 2 CO 3 nanosheets via a facile one-step hydrothermal method. Ternary TiO 2 /CuBi 2 O 4 /Bi 2 O 2 CO 3 (TCB) composites showed enhanced photocatalytic removal of tetracycline (TC), which is greater than pure Bi 2 O 2 CO 3 , CuBi 2 O 4 , TiO 2 and binary composites. The TCB-20 composite exhibited the best photo-degradation efficiency of TC (82% at 60 min) and maintained a higher stability after four consecutive cycles. Additionally, a dual Z-scheme photocatalytic mechanism with highly efficient and fast electron transfer was proposed, which prominently improves the photocatalytic performance. This work reports an integrated structure of a dual Z-scheme heterojunction that plays an important role in the degradation of tetracycline. Graphical abstract