Superprotonic conduction in metal–organic frameworks: Recent advances, design strategies, and mechanisms

Metal–organic frameworks (MOFs) have emerged as a highly promising class of crystalline proton-conducting materials owing to their designable structures, tunable pore environments, and well-defined conduction pathways. In recent years, superprotonic conduction in MOFs has become a major research focus, as an increasing number of MOF systems have achieved exceptionally high proton conductivities (>10 –2 S cm –1 ) with low activation energies. These advances indicate that superprotonic conduction arises from the cooperative interplay of abundant proton carriers, continuous hydrogen-bonding networks, and low-barrier conduction pathways. This review summarizes rational strategies to enhance proton conduction and highlights representative recent advances in superprotonic conduction in MOFs under both hydrated and anhydrous conditions, with the structure–property relationships underlying their outstanding performance discussed in detail. Finally, key challenges and future directions for the design of proton-conductive MOFs are presented.