Structural Engineering of Spinnable MOF Glasses via Shear-Induced Alignment of Embedded Metal-Hydroxide Nanobelts

Metal-organic framework (MOF) glasses have emerged as a promising class of materials owing to their unique combination of gas adsorption capabilities and superior moldability compared to conventional crystalline MOFs. However, their physical processing has remained largely constrained to powders or bulk monolithic solids. Inspired by the fiberization of conventional silica glasses that unlocked advanced functional architectures, developing a reliable processing strategy to draw MOF glasses into continuous fibers represents a critical frontier. Herein, we report a rational strategy to impart high spinnability to ZIF-62 (Zn(imidazole)1.75(benzimidazole)0.25) glasses through the in situ structural incorporation of one-dimensional (1D) γ-AlOOH nanobelts during the framework assembly. The composite glass containing an optimized 1 wt % fraction of γ-AlOOH exhibits enhanced fiber-drawing capability under tensile stress at elevated temperatures. This behavior is driven by the shear-induced alignment of the embedded nanobelts parallel to the stretching direction, mediated by interfacial interactions between the surface hydroxyl groups of γ-AlOOH and the imidazolate linkers, which successfully stabilizes the viscous MOF liquid matrix during elongation. The resulting composite glass fibers display mechanical resilience, enduring a bending curvature of 1.89 mm-1 at a diameter of 70 μm while fully preserving the intrinsic CO2 adsorption properties of the framework. This structural engineering of spinnable MOF glasses provides a versatile toolkit for fabricating advanced fibrous MOF architectures, opening up a wide horizon for mechanically resilient membrane filters, porous glass wool insulation, and intricate 3D structures.