Halogen lamp activated nanocomposites as nanoporous photocatalysts: Synthesis, characterization, and pollutant degradation mechanism

In this work, zeolitic imidazolate framework-8 (ZIF-8)-titania nanocomposites (ZT) with different amounts of titania nanoparticle (0.2, 0.4 and 0.6 g denoted as ZT-0.2, ZT-0.4 and ZT-0.6, respectively) as nanoporous photocatalysts were synthesized and characterized. A halogen lamp (500 W) was used as an irradiation source. The pollutant (Acid Blue 92 (AB92)) degradation mechanism was studied in details. The XRD, FTIR, SEM, TEM, BET, TGA and zeta potential were used to characterize the synthesized nanomaterials. The data showed that the ZT-0.4 nanocomposite had higher dye degradation ability due to the synergistic effect of ZIF-8 and titania. Dye degradation followed zero-order kinetics. The degradation rate of AB92 for 0.005, 0.010, 0.020 and 0.030 g of catalyst (ZT-0.4) was 0.00009, 0.00070, 0.00150 and 0.00190 mg/L min, respectively. The removal efficiency suggested that OH• possesses a major role for photocatalytic degradation of AB92. The synthesized nanocomposite showed stability and reusability over three cycles.