Tailorable Topologies for Selectively Controlling Crystals of Expanded Prussian Blue Analogues

Chemical manipulations of Prussian blues and Prussian blue analogues (PBAs) beyond first-row transition-metal cations have remained quite preliminary to this day. The presented report demonstrates the feasibility of using different types of cations, including general transition-metal ions, p region elements in the periodic table, lanthanide elements, and overlooked cations such as Al3+ and Mo3+ to build unique PBAs. A systematic study of the different types of PBAs is provided in terms of physical and chemical features by means of transition electron microscopy, X-ray photoelectron spectroscopy, and X-ray absorption near-edge structure. Diverse PBAs can be synthesized with different morphologies. The [Ni(CN)4]2–-based PBAs mainly exhibited layered products owing to their 4-fold-coordinated anions. The 6-fold-coordinated anion-based PBAs displayed cubic or distorted cubic crystal structures following the same method of ion arrangements with conventional [Fe(CN)6]2-/3–-based PBAs. Furthermore, bonding conditions are greatly affected by the introduced cations. In addition, the PBAs constructed using cations with more unpaired free electrons displayed intense paramagnetic performance. This study provides discoveries regarding innovative PBAs and gives new insights into materials exploration for different target applications.