Photocatalysts have offered a successful strategy for degrading organic pollutants, such as various dyes and antibiotics, in wastewater. In this study, the flower-like Bi2MoO6 balls were impregnated on the zirconium-based MOFs (MOF-801) to construct the Bi2MoO6/MOF-801 heterojunction composite photocatalytic materials through a simple one-pot hydrothermal method. The systematically characterization of the as-synthesized composite materials was performed using various analytical techniques, including XRD, FTIR, SEM-EDS, N2 adsorption⁃desorption testing, TG, XPS, UV-Vis DRS, PL, transient photocurrent, and EIS techniques, thereby confirming the successful impregnation of Bi2MoO6 into MOF-801. The degradation effect of the Bi2MoO6/MOF-801 composites on rhodamine B (RhB) dye was investigated, along with the photocatalytic degradation mechanism. Results showed that 0.1-Bi2MoO6/MOF-801 has better degradation efficiency for RhB dye than that of pure Bi2MoO6 and MOF-801 under visible light conditions, with a complete degradation efficiency of 98.1% achieved within 40 min. The boosted photocatalytic performance of the 0.1-Bi2MoO6/MOF-801 composite is attributed to their high specific surface area (529.2 m2/g) and mesoscale pore size (6.9 nm), wide visible spectral absorption, well-optimized band gap (2.81 eV), and the close contact of Bi2MoO6 and MOF-801 ensuring efficient charge separation and suppressing the recombination of photogenerated electron-hole pairs. Visible-light driven photocatalysis of 0.1-Bi2MoO6/MOF-801 composite further confirmed superior degradation of MB, AO, CR, MO, and ARS dyes, reaching degradation efficiencies up to 99.7%. Moreover, the results of the free radical capture experiments confirmed that the holes (h+) and superoxide radicals (•O2−), and electrons (e−) were the primary active substances during the degradation process, supporting the Z-scheme heterojunction charge transfer mechanism. This research study will point the direction for designing potential and affordable MOF-based heterojunction materials for the treatment of dye-contaminated wastewater.
Zhang et al. (Wed,) studied this question.