Preparation of Alkali Metal‐Doped MOF‐5@GO Composites and Study on Absorption Properties

Abstract The escalating CO 2 emissions from fossil fuel combustion demand advanced materials for efficient carbon capture. While metal–organic frameworks (MOFs) are promising for CO 2 adsorption, their limited thermal stability and moderate adsorption capacity hinder practical application. This work introduces a novel strategy by systematically incorporating alkali metal ions (Li + , Na + , K + ) into MOF‐5@GO composites to synergistically enhance structural robustness and adsorption performance. Especially, the Li doped MOF‐5@GO composite material shows the most promising performance. The threshold effect of Li ion doping ratios on framework integrity revealed that optimal Li + doping (3%) optimizes pore structure without structural degradation, while excessive doping (>3%) induces pore blockage and lattice distortion. The 3Li‐MOF‐5@GO composite achieved remarkable improvements: with a 52.53% increase in specific surface area (1369.52 m 2 /g) and a 66.14% enhancement in CO 2 adsorption capacity (98.32 cm 3 /g at 298 K, 0.1 MPa), coupling with a thermal decomposition temperature of 567 °C. Mechanistic studies via XRD, FTIR, and XPS demonstrates that Li + , with its minimal ionic radius and high charge density, strengthens Zn─O coordination bonds, elevates thermal resistance, and amplifies electrostatic interactions with CO 2 quadrupoles. This study establishes alkali metal doping as a transformative approach for engineering MOF‐based adsorbents, offering a scalable pathway toward high‐performance carbon capture technologies to mitigate global warming.