Fraccarollo Alberto, Canti Lorenzo, Marchese Leonardo, Cossi Maurizio
Dipartimento di Scienze e Innovazione Tecnologica (DISIT), Centro Interdisciplinare Nano-SiSTeMI, Università del Piemonte Orientale , via T. Michel 11, I-15121, Alessandria, Italy.
Langmuir. 2014 Apr 15;30(14):4147-56. doi: 10.1021/la500111a. Epub 2014 Apr 1.
The adsorption isotherms of CO2 in several porous aromatic frameworks (PAFs) have been simulated with Grand Canonical Monte Carlo technique, to support the synthesis of new materials for efficient carbon dioxide capture and storage. The simulations covered the 0-60 bar pressure range and were repeated at 273, 298, and 323 K. The force field employed in the simulations was optimized to fit the correct behavior of the free gas and to reproduce the CO2-phenyl interactions computed at high quantum mechanical level. PAFs are based on the diamond structure, with polyaromatic chains inserted in C-C bonds. We examined four PAF-30n (n being the number of phenyl rings in the aromatic linkers), finding that PAF-302 is overall the best performing, although PAF-301 provides higher adsorbed densities at very low pressure. The CO2 adsorption then was simulated in a number of modified PAF-302, with different functional groups (aminomethane, toluene, pyridine, and imidazole) attached to the phenyl chains; different degrees of substitution (25%, 50%, and 100% derivatized rings) were considered. The effects of functionalization and the dependence on the substitution degree are carefully discussed, to determine the most promising materials at low, intermediate, and high pressures.
利用巨正则蒙特卡罗技术模拟了二氧化碳在几种多孔芳香骨架材料（PAFs）中的吸附等温线，以支持合成用于高效二氧化碳捕获和储存的新材料。模拟涵盖了0至60巴的压力范围，并在273K、298K和323K下重复进行。模拟中使用的力场经过优化，以符合自由气体的正确行为，并重现高量子力学水平下计算的二氧化碳与苯基之间的相互作用。PAFs基于金刚石结构，在碳 - 碳键中插入了多芳香链。我们研究了四种PAF - 30n（n为芳香连接体中苯环的数量），发现尽管PAF - 301在极低压力下提供更高的吸附密度，但总体而言PAF - 302表现最佳。然后在一些改性的PAF - 302中模拟了二氧化碳吸附情况，这些PAF - 302的苯链上连接了不同的官能团（氨基甲烷、甲苯、吡啶和咪唑）；考虑了不同程度的取代（25%、50%和100%衍生化环）。仔细讨论了官能化的影响以及对取代度的依赖性，以确定在低、中、高压下最有前景的材料。
