Bioinspired Metal–Organic Framework for Trace CO2 Capture

A Zn benzotriazolate metal–organic framework (MOF), [Zn­(ZnO2CCH3)4(bibta)3] (1, bibta2– = 5,5′-bibenzotriazolate), has been subjected to a mild CH3CO2–/HCO3– ligand exchange procedure followed by thermal activation to generate nucleophilic Zn–OH groups that resemble the active site of α-carbonic anhydrase. The postsynthetically modified MOF, [Zn­(ZnOH)4(bibta)3] (2*), exhibits excellent performance for trace CO2 capture and can be regenerated at mild temperatures. IR spectroscopic data and density functional theory (DFT) calculations reveal that intercluster hydrogen bonding interactions augment a Zn–OH/Zn–O2COH fixation mechanism.一种苯并三氮唑锌基金属有机框架（metal–organic framework, MOF），化学式为[Zn(ZnO₂CCH₃)₄(bibta)₃]（编号1，bibta²⁻ = 5,5'-联苯并三氮唑二阴离子），经温和的CH₃CO₂⁻/HCO₃⁻配体交换过程处理后再进行热活化，可生成类似α-碳酸酐酶活性位点的亲核性Zn-OH基团。该经合成后修饰的MOF，化学式为[Zn(ZnOH)₄(bibta)₃]（编号2*），对痕量CO₂捕集表现出优异性能，且可在温和温度下实现再生。红外光谱（infrared spectroscopy, IR）数据与密度泛函理论（density functional theory, DFT）计算结果表明，团簇间氢键相互作用可增强Zn-OH/Zn-O₂COH的CO₂固定机制。