Synthesis of stable single-crystalline carbon dioxide clathrate powder by pressure swing crystallization

Reversible CO2 capture and release under ambient conditions is crucial for energy-efficient carbon storage. Here, we report the pressure swing crystallization of in a single-crystalline guanidinium sulfate-based clathrate salt practical 52 kPa 298 K, with high density (0.252 g cm−3) capacity (17 wt %). The captured released as pure stream through moderate means or temperature stimulation, all while desorbed Gua2SO4 ready another cycle. selective exclusively to even presence common flue gas components, such water vapor N2, owing specific electrostatic interaction between cations. mechanism unraveled single-crystal studies distinctively different from physisorption chemisorption, opening up promising venue future storage technologies rapid solidification using an abundant salt.