Proton conductive Zr-based MOFs

The applications of crystalline solid-state proton conductive materials in fuel cells, proton sieving, electrochemical sensing and biochemistry are in the foreground, among which proton conducting metal–organic frameworks are favored by researchers for their structural diversity, functional design and modification. As one class of promising candidates for proton conductors, Zr-based metal–organic frameworks (MOFs) have attracted considerable attention. Therefore, the proton conductivity of such complexes will be comprehensively summarized for the first time by us. Herein, the proton conductivity properties of these MOFs with ordered porous structures, outstanding thermal stability, remarkably high water stability and chemical stability will be reviewed. These MOFs are classified and summarized according to the types of constructed organic ligands, such as carboxylic, phosphoric, and nitrogenous ligands. Consequently, the preparation strategy, structural characteristics, proton conductivity, conduction mechanism and application value are discussed. Finally, based on our experimental experience and literature review, the future development direction and application of this type of proton conducting MOF are assessed and highlighted.