Two‐Dimensional Frameworks From Metal Oxo Clusters at Liquid Interfaces

We report the realization of a two‐dimensional analog of the archetypical metal‐organic framework UiO‐66 as a Langmuir monolayer, constructed from preformed metal oxo clusters and amphiphilic terephthalic acid ligands at the air–water interface. Structural changes of the metal oxo clusters in aqueous solution were elucidated to clarify their role in interfacial self‐assembly at the water surface. Langmuir balance studies demonstrated that self‐assembly with specifically designed organic linkers proceeds through a coordination‐driven process. The resulting films were characterized by complementary techniques to determine their morphology, thickness, and composition. Based on these findings, a packing model of the monolayer was proposed. Finally, we extended this coordination‐driven self‐assembly strategy beyond aqueous systems to form, for the first time, monolayers at the air– N , N ‐dimethylformamide interface.