Pore Environment Optimization of Microporous Metal–Organic Frameworks with Huddled Pyrazine Pillars for C2H2/CO2 Separation

• DOI: 10.1021/acsami.2c19779
• Publication Date: 2023-01-10T13:35:05Z
• Authors: Yong-Zheng Zhang; Xiang-Jing Kong; Wen-Feng Zhou; Chun-Hui Li; Hui Hu; Hengnuo Hou; Zhongmin Liu; Longlong Geng; Hongliang Huang; Xiuling Zhang; Da-Shuai Zhang; Jian-Rong Li
• Keywords: Pyrazine; Isostructural; MXenes

Metal-organic frameworks (MOFs) have been proven promising in addressing many critical issues related to gas separation and purification. However, it remains a great challenge optimize the pore environment of MOFs for purification specific mixtures. Herein, we report rational construction three isostructural microporous with 4,4',4"-tricarboxyltriphenylamine (H3TCA) ligand, unusual hexaprismane Ni6O6 cluster, functionalized pyrazine pillars [PYZ-x, x = -H (DZU-10), -NH2 (DZU-11), -OH (DZU-12)], where building blocks clusters huddled are reported porous first time. These enabled resulting materials exhibit good chemical stability variable chemistry, which thus contribute distinct performances toward C2H2/CO2 separation. Both single-component isotherms dynamic column breakthrough experiments demonstrate that DZU-11 PYZ-NH2 pillar outperforms its hydrogen hydroxy analogues. Density functional theory calculations reveal higher C2H2 affinity over CO2 is attributed multiple electrostatic interactions between framework, including strong C≡C···H-N (2.80 Å) interactions. This work highlights potential optimization construct smart MOF adsorbents some challenging separations.