Co-precipitation synthesis of reusable ZnAl-CLDH/ZIF-8 heterojunction for enhanced photodegradation of organic dye

The ZnAl calcined layered double hydroxides/ZIF-8 composites (ZnAl-CLDH/ZIF-8) were successfully synthesized by a simple and efficient co-precipitation method. Characterizations including XRD, SEM, XPS, UV–vis DRS and EIS were used to investigate the structures and the morphologies of the fabricated photocatalysts. Furthermore, the photocatalytic properties of the composites were evaluated by the photodegradation of Methyl blue (MB) under irradiation. The catalyst showed a high efficiency (97.35%) at the mass ratio of ZIF-8 was 5%. It is worth mentioning that the removal efficiency of MB is still higher than 90% for reused ZnAl-CLDH/ZIF-8 after five cycle runs, confirming the promising practical application. Based on the experimental results, a possible mechanism of decomposition of MB by the ZnAl-CLDH/ZIF-8 heterojunction was proposed.