胺基功能化的炭材料上二氧化碳吸附的密度泛函理论研究（英文）

Density Functional Theory Study of CO_2 Adsorption in Amine-Functionalized Carbonaceous Materials

本文利用色散作用校正的密度泛函理论研究了炭材料上含氮官能团对CO_2吸附的作用。通过计算比较了不同含氮官能团炭材料结构片段吸附二氧化碳后的结构参数和能量,由于较强的静电作用和形成弱氢键,含单个苯环的酰胺和吡啶类的吸附剂吸附二氧化碳的作用强于单个苯胺和吡咯类吸附剂。但当增加苯环数时,色散作用主导的吡咯型吸附剂的吸附能力显著增强。以上结果预示着酰胺和吡咯类将是大π体系中具有良好CO_2吸附性能的吸附剂。因而,色散作用在CO_2吸附过程中也占据着重要地位。计算得到的结果与我们之前的实验结果一致,并且将有利于筛选更有效的二氧化碳吸附剂。

Density functional theory with dispersion correction（DFT-D3） was used to investigate the effects of N-doping on the adsorption of CO2 in carbonaceous materials. The CO2 adsorption energies and equilibrium geometry parameters were studied to compare the effects of various N-containing functional groups. The adsorption energies of single amide- and pyridine-type adsorbents were higher than those of aniline- and pyrroletype adsorbents, as a result of strong electrostatic interactions and/or the formation of weak hydrogen bonds.For pyrrole-type adsorbents, the adsorption energy increased with increasing number of benzene rings, because dispersion became the dominant interaction. These findings indicate that amide- and pyrrole-type adsorbents are the most promising CO2 trappers. The calculation results are consistent with our previous experimental conclusions for N-doped carbonaceous materials and will be useful for screening carbon materials to achieve more efficient CO2 capture.