Hu Fengyu, Zhu Rencheng
School of Civil Engineering and Architecture, Zhengzhou Urban Construction Vocational College, Zhengzhou, 450052, China.
School of Ecology and Environment, Zhengzhou University, No.100 Science Avenue, Zhengzhou, 450001, China.
J Mol Model. 2024 Jan 19;30(2):44. doi: 10.1007/s00894-024-05844-0.
To explore the impact of OGs (OGs) on formaldehyde (HCHO) adsorption by modified activated carbon, this paper studied the influence of OGs on HCHO adsorption characteristics, varying the groups including ester, carboxyl, and hydroxyl. Employing density functional theory (DFT), the effects of various OGs on the structure of N-doped activated carbon through GGA-PBE exchange-correlation functionals by Materials Studio combined with Gaussian software. The types of weak interactions during the adsorption process were calculated by RDG, elucidating the mechanism through which the three OGs affect HCHO adsorption on N-doped activated carbon. The dynamic adsorption process of HCHO was simulated by molecular dynamics (MD). The influence and proportion of OGs on HCHO adsorption were subsequently analyzed using van der Waals and electrostatic interactions, determining differences in formaldehyde adsorption effects across OG types. The carboxyl group exhibits the most robust synergistic adsorption effect on the modified activated carbon. There is a notable alteration in the position and distribution of electrostatic potential extremes observed following carboxyl modification. The calculation results show that the adsorption energy of hydroxyl groups on modified activated carbon is the highest, at -5.07 kcal/mol, with a transfer charge of 0.014 e. Following the introduction of carboxyl groups, the proportion of electrostatic interactions escalated from the initial 24% to 38%. This study will provide new ideas for guiding the design of activated carbon for efficient adsorption of formaldehyde.
The modified activated carbon fragments of three OGs were constructed by Materials Studio and Gaussian software, and the surface electrostatic potential polarity and area distribution, charge change, adsorption energy, and transferred charge of each molecular fragment were calculated. Moreover, cell models of OGs with the same dimensions were constructed to simulate the adsorption amount, heat of adsorption, interaction energy, radial distribution function, and hydrogen-bonding interactions for methane at room temperature and pressure. The results were consistent with the DFT simulations.
为探究含氧基团（OGs）对改性活性炭吸附甲醛（HCHO）的影响，本文研究了OGs对HCHO吸附特性的影响，改变的基团包括酯基、羧基和羟基。采用密度泛函理论（DFT），通过Materials Studio结合高斯软件的GGA-PBE交换相关泛函，研究了各种OGs对氮掺杂活性炭结构的影响。通过RDG计算吸附过程中的弱相互作用类型，阐明了三种OGs影响HCHO在氮掺杂活性炭上吸附的机制。采用分子动力学（MD）模拟了HCHO的动态吸附过程。随后利用范德华力和静电相互作用分析了OGs对HCHO吸附的影响及比例，确定了不同类型OGs对甲醛吸附效果的差异。羧基对改性活性炭表现出最强的协同吸附作用。羧基改性后，静电势极值的位置和分布有显著变化。计算结果表明，改性活性炭上羟基的吸附能最高，为-5.07 kcal/mol，转移电荷为0.014 e。引入羧基后，静电相互作用的比例从最初的24%升至38%。本研究将为指导高效吸附甲醛的活性炭设计提供新思路。
利用Materials Studio和高斯软件构建了三种OGs的改性活性炭片段，计算了各分子片段的表面静电势极性和面积分布、电荷变化、吸附能和转移电荷。此外，构建了相同尺寸的OGs的晶胞模型，模拟了室温常压下甲烷的吸附量、吸附热、相互作用能、径向分布函数和氢键相互作用。结果与DFT模拟结果一致。
