One-pot hydrothermal synthesis of TiO2/UiO-67 for highly efficient photocatalytic degradation of Rhodamine B

Background The selection of suitable semiconductor materials to enhance TiO 2 photocatalytic performance requires further investigation. Metal-organic frameworks (MOFs) are promising novel semiconductors with broad application potential, but a more convenient and efficient method for synthesizing TiO 2 /MOF composites is urgently needed. Methods Herein, a simple one-step hydrothermal approach for synthesizing TiO 2 /UiO-67 composites with tunable Ti/Zr molar ratios was reported. The formation of a type II heterojunction between TiO 2 and UiO-67 was confirmed by various characterization techniques. Significant findings UT50 (Ti:Zr molar ratio = 50) exhibited excellent photodegradation performance toward the organic pollutant rhodamine B (RhB), achieving 98.33 % degradation within 90 min under visible light. Its apparent rate constant (0.0454 min⁻¹) was 1.6 times higher than that of UiO-67 and 5.3 times higher than that of TiO 2 . The enhanced catalytic performance was primarily attributed to the effective generation of photo-induced electrons and the high efficiency of charge separation. Moreover, the degradation efficiency remained consistently high over four consecutive cycles with no significant decline. •O 2 — and h + were the predominant active species based on the radical trapping and EPR experiments. This study provides new insights into the development of efficient TiO 2 /MOF photocatalysts in environmental pollution cleanup.