Synthesis of BiOI/ZnCo-CLDH hybrid photocatalyst with highly efficient degradation of rhodamine B and tetracycline hydrochloride

A visible-light-responsive hybrid photocatalyst, the BiOI/calcined ZnCo-layered double hydroxides (BiOI/ZnCo-CLDH), has been prepared via hydrothermal method. The property of samples was characterized by XRD, SEM, FT-IR, UV-vis and XPS, respectively. The photocatalytic activity of BiOI/ZnCo-CLDH was investigated by photodegradation of rhodamine B (RhB) and tetracycline hydrochloride (TCH) under visible light. The BiOI/ZnCo-CLDH hybrid photocatalyst which contains ZnCo-CLDH with mass fraction of 5wt% (BiOI/CLDH-3) shows the best degradation efficiency of RhB and TCH. The degradation efficiency of RhB (10 mg/L) can be achieved to 99.73 % in 40 min and the degradation efficiency of TCH (20 mg/L) can be achieved to 86.60 % in 90 min. Furthermore, the capture experiment demonstrates that h⁺ and ·OH are the primary active substance and the auxiliary active substance in the system of reaction, respectively. After five degradation experiments, the degradation efficiency of RhB and TCH by the composites can still achieve to 86 % of its initial activity, proving that the composites have remarkable reusability and stability.