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

在环境条件下可逆的CO ₂捕获和释放对于节能碳捕获和储存至关重要。_{在这里，我们报告了在 52 kPa 和 298 K 的实际条件下，CO 2}在单晶硫酸胍基笼形盐中的变压结晶，具有高 CO ₂密度（0.252 g cm ^-3）和容量（17 wt %)。捕获的 CO ₂通过适度的压力或温度刺激以纯流形式释放，同时解吸的 Gua ₂ SO ₄准备好进行另一个循环。包合物对 CO _{2具有特异性选择性}由于 CO 2 和胍阳离子之间的特定静电相互作用_，即使_存在常见的烟道气成分（例如水蒸气和 N 2 ） 。通过单晶研究揭示的机制与物理吸附或化学吸附截然不同，通过使用丰富的盐快速固化 CO ₂为未来的碳捕获和储存技术开辟了一个有前途的场所。