A [Zn₃]-cluster-based MOF catalyst for highly efficient and recyclable CO₂ conversion into cyclic carbonates

The catalytic conversion of CO₂ into value-added cyclic carbonates offers a sustainable route for carbon utilization, combining 100% atom economy with industrial relevance in polymer, electrolyte, and solvent applications. Herein, we report a novel [Zn₃]-cluster-based framework (Zn-BTB) through a two-step synthetic strategy. Zn-BTB with a porous framework shows a high BET surface area of 523.86 m² g^-1 and CO₂ adsorption capacities of 41.56 cm³ g^-1 at 273 K and 23.38 cm³ g^-1 at 298 K. Zn-BTB exhibits high stability under various conditions, including organic solvents, a broad pH range (1-13), and thermostability up to 422 °C. These results enable its high performance in catalytic CO₂ cycloaddition conversion with epoxides, achieving over 80% yields of various cyclic carbonates. Notably, Zn-BTB maintains its catalytic performance over eight consecutive cycles without significant degradation. This work presents a two-step strategy for designing robust cluster-based MOFs with hierarchical porosity, demonstrating strong potential for sustainable catalytic applications for CO₂ conversion.