Designing bipyridine-functionalized zirconium metal–organic frameworks as a platform for clean energy and other emerging applications

Metal–organic frameworks (MOFs) are a class of crystalline and porous materials with modular structural features. This modularity has allowed MOFs to be designed and synthesized with adjustable pore sizes and shapes leading to ultrahigh porosity. Among the tens of thousands of known MOF structures, zirconium-based MOFs (Zr-MOFs) have attracted attention not only for their structural properties but also their superior chemical and thermal stabilities, which are critical for a myriad of practical applications. In particular, bipyridine (BPY) functionalized Zr-MOFs have been received recognition for their interesting intrinsic properties, which arise from various post-modification pathways. The fact that post-modification is readily available for such MOFs paves the way towards anchoring specific components (functional groups, metals complexes, and nanoparticles) via the bipyridine docking centers, thus endowing this MOF platform with the capability to chemically alter and enhance the bulk material’s properties. Throughout this review, an emphasis is placed on the preparation of BPY-functionalized Zr-MOFs, their characterization, and subsequent applications, such as electrocatalytic or photocatalytic hydrogen evolution reactions, heterogeneous molecular catalysis, and gas storage for renewable energy. Furthermore, this review highlights the design and applications of materials from the viewpoint of materials design and the necessity and importance of installing complexity to achieve synergistic interactions. Finally, our perspective for future applications is introduced with the expectation of providing useful information to those interested in this specific MOF platform.