Design strategies of chitosan/metal organic frameworks composites for CO₂ capture: a review

Chitosan (CS) has emerged as an effective platform for integrating metal–organic frameworks (MOFs), combining the large surface area and tunable structures of MOFs with the amine-rich functionality and processability of CS. These synergistic features promote strong interfacial interactions and allow the composite to be shaped into membranes, beads, and gels, yielding composites with enhanced mechanical stability, dispersibility, and recyclability that overcome key limitations of pristine MOFs. In response to the urgent need for efficient CO₂ capture technologies, this review provides a comprehensive evaluation of CS/MOF composites for CO₂ capture. It examines how interfacial interactions, adsorption mechanisms, and synthesis parameters influence CO₂ adsorption and separation performance. Relationships between surface area, pore architecture, open metal sites and functionalisation are critically analysed to optimising CS/MOF composites performance. Key challenges and future directions are also discussed, including material stability, scalability, environmental sustainability, and life-cycle assessments to support industrial implementation.