Abstract：
Excessive CO2 in the air can not only lead to serious climate problems but also cause serious damage to humans in confined spaces. Here, a novel metal-organic framework (FJI-H38) with adaptive ultramicropores and multiple active sites is prepared. It can sieve CO2 from air with the very high adsorption capacity/selectivity but the lowest adsorption enthalpy among the reported physical adsorbents. Such excellent adsorption performances can be retained even at high humidity. Mechanistic studies show that the polar ultramicropore is very suitable for molecular sieving of CO2 from N2 , and the distinguishable adsorption sites for H2 O and CO2 enable them to be co-adsorbed. Notably, the adsorbed-CO2 -driven pore shrinkage can further promote CO2 capture while the adsorbed-H2 O-induced phase transitions in turn inhibit H2 O adsorption. Moreover, FJI-H38 has excellent stability and recyclability and can be synthesized on a large scale, making it a practical trace CO2 adsorbent. This will provide a new strategy for developing practical adsorbents for CO2 capture from the air.
摘要：
空气中过量的二氧化碳不仅会导致严重的气候问题，还会对密闭空间中的人类造成严重损害。这里,制备了具有自适应超微孔和多个活性位点的新型金属有机框架（FJI-H38）。它可以从空气中筛选CO2，具有很高的吸附容量/选择性，但在所报道的物理吸附剂中吸附焓最低。即使在高湿度下也可以保持这种优异的吸附性能。机理研究表明，极性超微孔非常适合从N2中进行CO2的分子筛分，H2O和CO2的可区分吸附位点使它们能够共吸附。值得注意的是,吸附CO2驱动的孔收缩可以进一步促进CO2的捕获，而吸附H2O诱导的相变又抑制H2O的吸附。此外，FJI-H38具有优异的稳定性和可回收性，可大规模合成，使其成为一种实用的痕量CO2吸附剂。这将为开发用于从空气中捕获CO2的实用吸附剂提供新的策略。
