Design Strategies and Application Prospects of Metal–Organic Framework/Carbon-Based Composite Adsorbents

Abstract

Metal-Organic Frameworks (MOFs) are coordination polymers formed by the self-assembly of organic ligands and transition metal ions through coordination bonds, hydrogen bonds, or other weak intermolecular interactions, resulting in one-, two-, or three-dimensional structures. MOFs exhibit high specific surface areas, porous architectures, and tunable functionalities. However, they still face several limitations, including brittleness, poor film-forming ability, low mechanical strength, limited processability, and structural instability under humid or high-temperature conditions. The integration of carbon materials with MOFs can effectively compensate for the poor mechanical strength, aggregation tendency, and limited selective adsorption of MOFs by introducing structural stability, enhanced conductivity, and hierarchical porosity, owing to the robust frameworks of CNTs, the dispersion capability of graphene, and the high surface accessibility of activated carbon. This review summarizes several synthesis strategies for carbon-based material/MOF composites, including in situ growth, electrostatic self-assembly, impregnation, post-treatment, and surface modification. Additionally, it discusses their adsorption performance for ions such as Cd²⁺, Ni²⁺, and As⁵⁺, as well as their potential applications in fields like wastewater treatment.