Time-Temperature Superposition Principle Serving as a Design Tool for Tailored MOF-Crystal Glass Composite Membranes

Metal-organic framework (MOF) glass membranes demonstrate promising potential in the field of gas separation. This study presents the time-temperature superposition (TTS) principle to guide the fabrication of MOF-based crystalline-glass composite (CGC) membranes, addressing the critical challenge of thermal degradation of fillers during processing. Using glassy ZIF-62 as the continuous phase and crystalline UiO-66, Mg-MOF-74, and MOF-801 as dispersed phases, three types of MOF-based CGC membranes were successfully prepared through precise regulation of processing temperature and time, with minimal thermal decomposition. These membranes exhibit high separation efficiency for CO2/N2, CH4/N2, and C4 hydrocarbon mixtures. The TTS-assisted low-temperature remelting strategy establishes a versatile and tailorable platform for developing fresh CGC materials, opening additional pathways for expanding the family of CGC composites. Here authors present a time-temperature superposition strategy to fabricate MOF-based crystalline-glass composite membranes at low temperatures without thermal degradation, with which three membranes are engineered for efficient gas separation.