Jia Weimin, Qi Bomiao, Wang Yanbin, Lu Zhibin, Wang Jiqian, Su Qiong, Nian Jingyan, Liang Junxi
School of Chemical Engineering, Northwest Minzu University, Lanzhou 730030, China.
State Key Lab Solid Lubricat, Lanzhou Institute of Chemical Physics, Lanzhou 730000, China.
Molecules. 2023 Jul 14;28(14):5417. doi: 10.3390/molecules28145417.
The interfacial mechanism has always been a concern for 3-aminopropyltriethoxysilane (APTES)-grafted palygorskite (PAL). In this research, the mechanism of graft modification for grafting of APTES to the surface of PAL (100) was studied using density functional theory (DFT) calculation. The results illustrated that different grafting states of the APTES influence the inter- and intramolecular interactions between APTES/PAL (100), which are reflected in the electronic structures. For single-, double-, and three-toothed state APTES-PAL (100), the charge transfer rates from the PAL (100) surface to APTES were 0.68, 1.02, and 0.77 e, respectively. The binding energy results show that PAL (100) modification performance in the double-tooth state is the best compared to the other states, with the lowest value of -181.91 kJ/mol. The double-toothed state has lower barrier energy (94.69, 63.11, and 153.67 kJ/mol) during the modification process. This study offers theoretical insights into the chemical modification of the PAL (100) surface using APTES coupling agents, and can provide a guide for practical applications.
界面机制一直是3-氨丙基三乙氧基硅烷（APTES）接枝坡缕石（PAL）所关注的问题。在本研究中，利用密度泛函理论（DFT）计算研究了APTES接枝到PAL（100）表面的接枝改性机理。结果表明，APTES的不同接枝状态影响了APTES/PAL（100）之间的分子间和分子内相互作用，这在电子结构中有所体现。对于单齿、双齿和三齿状态的APTES-PAL（100），从PAL（100）表面到APTES的电荷转移速率分别为0.68、1.02和0.77 e。结合能结果表明，与其他状态相比，双齿状态下PAL（100）的改性性能最佳，最低值为-181.91 kJ/mol。在改性过程中，双齿状态具有较低的势垒能量（94.69、63.11和153.67 kJ/mol）。本研究为使用APTES偶联剂对PAL（100）表面进行化学改性提供了理论见解，并可为实际应用提供指导。
