碱金属修饰的萘炔/萘二炔对CO_(2)选择性吸附分离的理论计算

Theoretical calculation of selective adsorption and separation of CO_(2) by alkali metal modified naphthalene/naphthalenediyne

采用巨正则蒙特卡洛模拟和密度泛函理论结合的方式探究了不同碱金属(alkali metal,AM,包括Li、Na、K)修饰提升萘炔(naphyne,NY)和萘二炔(naphdiyne,NDY)的CO_(2)吸附分离性能。通过结合能和结构的电子性质分析发现,AM修饰的NY和NDY具有良好的结构稳定性。在298 K、100 k Pa的条件下,Li修饰的萘二炔(Li-NDY)表现出高达11.37 mmol·g^(-1)的CO_(2)吸附量和430.85的CO_(2)选择性(优于N_(2))。同时,利用气体吸附密度分布揭示了不同AM修饰的NY/NDY(AM-NY、AM-NDY)具有高吸附量的原因,以及二者作用效果差异的本质。最后,从吸附热、库仑和范德瓦耳斯相互作用等角度详细说明了AM引入的改性机制。

In this study,a combination of grand canonical Monte Carlo and density functional theory was employed to investigate the CO_(2) adsorption and separation behavior of naphyne(NY)and naphdiyne(NDY)with different alka-li metal(AM,including Li,Na,and K)dopants.By analyzing the binding energy,cohesive energy,and electronic properties,it is found that AM-modified NY and NDY exhibit good structural stability.Under conditions of 298 K and 100 kPa,Li-NDY(the NDY modified by Li),exhibits a CO_(2) adsorption capacity of 11.37 mmol·g^(-1),with a selec-tivity for CO_(2) over N_(2) of 430.85.Furthermore,the gas adsorption density distribution elucidates the reasons behind the high adsorption capacity of AM-NY and AM-NDY and the inherent difference in their performance.Finally,the modified mechanisms introduced by the AM dopants were discussed in detail from the perspectives of adsorption heat,Coulomb and van der Waals interactions,and other factors.