Hydrolytic Stability of Metal–Organic Frameworks: An Experimental Study
Ankit K. Yadav, Megan N. Kenny, Emmanuel N. Musa, Timothy J. Walz, Andrzej Gładysiak, Kyriakos C. Stylianou
Abstract
Metal–organic frameworks (MOFs) are widely explored for applications involving direct contact with water, such as carbon dioxide capture and utilization, photocatalytic hydrogen evolution, and water purification. However, many MOFs are prone to degradation via hydrolysis of metal–ligand coordination bonds, leading to inferior performance and casting doubt on their long-term viability in aqueous environments. Current literature has employed a wide variety of methods to evaluate the hydrolytic stability of MOFs when they are exposed to water, leading to difficulties in comparing different materials. Herein, we establish a systematic and reproducible experimental protocol to evaluate the hydrolytic stability of fifty-one (51) porous materials─including 50 (50) MOFs and one (1) zeolite─synthesized in our laboratory. Each material was subjected to liquid water exposure under standardized conditions, followed by characterization of structural integrity (via powder X-ray diffraction), porosity (via 77 K nitrogen adsorption and CO 2 uptake at 298 K), and mass retention (via thermogravimetric analysis). This screening reveals high water stability in several MOFs─including most aluminum-based MOFs, MIL-101(Cr), m CBMOF-1, ZIF-301, ZIF-zni, MIL-167, CALF-20, and zeolite 13X─while identifying other materials, such as UiO-67, UiO-68, and MIL-125-NH 2, as susceptible to partial or complete degradation. Our work offers a critical benchmark for the field and underscores the importance of prescreening hydrolytic stability in the development of MOFs for aqueous-phase applications. It also advocates for standardization in stability testing to enable clear comparison of materials for real-world deployment.