Advances and Challenges in the Development of Three-Dimensional Nickel-Centered Metal-Organic Frameworks Engineered via Carboxylate-Based Bridging Ligands.

As a prominent and extensively investigated subclass of metal-organic frameworks (MOFs), specifically those constructed from divalent transition metals, three-dimensional (3D) nickel-carboxylate MOFs have attracted considerable scientific attention due to their distinctive structural characteristics and multifunctional properties. The d8 electronic configuration of Ni(II) ions confers unique coordination preferences, enabling the formation of robust, highly interconnected 3D architectures featuring diverse topological motifs, tunable porosity, and accessible coordinatively unsaturated open metal sites. Complemented by strong host-guest interactions, pronounced magnetic anisotropy, and efficient redox activity, these structural features synergistically underpin the exceptional performance of 3D Ni-carboxylate MOFs across a wide range of advanced applications. This review presents a systematic account of the development of carboxylate-based 3D Ni-MOFs, encompassing key synthetic methodologies, principles of structural classification, and their applications in gas adsorption and separation, heterogeneous catalysis, chemical sensing, and magnetic materials. Finally, we critically assess current challenges and outline promising future directions for the rational design and functional optimization of this compelling class of materials.