Gas transformations within metal-organic cages.

The efficient transformation of gaseous molecules into value-added products remains a central challenge in sustainable chemistry, limited by the low reactivity of some gases and the complexity of achieving product selectivity. Metal-organic cages (MOCs), with their tunable cavities and dynamic host-guest interactions, have emerged as promising platforms for gas conversion, leveraging confinement effects to enhance reactivity and selectivity. This contribution highlights recent advances in MOC-mediated gas transformations-including photocatalytic O2 reduction, electrochemical CO2 conversion to combustible gases, H2S splitting for H2 generation, and SO2 oxidation and mineralization-illustrating how spatial arrangement, co-encapsulation of catalysts and substrates, and cavity design unlock new reaction pathways under mild conditions. Mechanistic insights and structural features outline design principles for next-generation cage-based systems. Ultimately, MOCs offer molecular precision to bridge homogeneous and heterogeneous catalysis, with profound implications for the development of complex gas-liquid-solid phase reactions and transformative technologies aimed at addressing some of the most critical challenges in environmental remediation, energy generation, and circular manufacturing.