Metallized hydrogen-bonded frameworks: From strategic construction to functional applications

Metallized hydrogen-bonded organic frameworks (HOFs) are a rapidly emerging class of functional porous materials created by integrating metal centers into hydrogen-bonded supramolecular architectures. This review systematically categorizes and analyzes the construction and applications of metallized HOFs, covering neutral metal-complex HOFs (M-HOFs), ionic M-HOFs, metal halide HOFs (MX-HOFs), and supramolecular HOFs (S-HOFs). By examining the distinct roles of metals, from serving as structural templates that guide hydrogen-bonding networks and stabilize topologies to acting as functional sources of electronic, catalytic, and magnetic activity, we clarify the fundamental design principles of these hybrid materials. The intentional metallization strategy addresses the structural instability of purely organic HOFs while synergistically merging the dynamic, reversible hydrogen-bonded networks with the versatile functionality of metal centers. This integration facilitates precise control over porosity, pore chemistry, and framework adaptability, enabling outstanding performance in a wide range of applications, such as gas separation and purification, catalysis (including photocatalysis, electrocatalysis, and asymmetric catalysis), proton conduction, sensing, bioimaging, and therapeutic interventions. This review aims to establish a unified mechanistic perspective on structure-property-function relationships in metallized HOFs and to emphasize their potential as a flexible platform for next-generation adaptive and multifunctional materials.