Rapid Synthesis of MIV-Based Multimetal–Organic Frameworks for Photopolymerization of Methyl Methacrylate under Visible Light

Metal–organic frameworks (MOFs) are porous materials that have attracted increasing interest for photocatalytic applications. Conventional solvothermal synthesis of photoactive MOFs typically requires high-pressure reactors and time-consuming preparative protocols. This study reports the preparation of Ti-, Zr-, and/or Hf-based MOFs using a hot injection approach. Among the prepared materials, NH 2 -UiO-66 (Zr/Hf) exhibited high photocatalytic activity for the polymerization of methyl methacrylate under visible light irradiation and under monochromatic visible light at a wavelength of 430 nm (xenon lamp or light-emitting diode). The ability to produce these materials using simple, low-pressure equipment makes this method a promising route for process scale-up and cost reduction. The obtained MOFs demonstrated high photostability, maintaining nearly unchanged activity over three photocatalytic cycles and during long-term operation (44 h). Moreover, the polymer products were analyzed via size exclusion chromatography and complementary analytical techniques, thereby elucidating the photopolymerization process under different irradiation conditions and reaction times.