Panczyk Tomasz, Wolski Pawel, Nieszporek Krzysztof, Pietrzak Robert
Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, ul. Niezapominajek 8, 30239 Cracow, Poland.
Department of Theoretical Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University, Lublin pl. Maria Curie-Sklodowska 3, 20031 Lublin, Poland.
Molecules. 2024 Dec 21;29(24):6030. doi: 10.3390/molecules29246030.
This study explores the formation of functionalized carbon surfaces through shock compression of graphite in the presence of water, modeled using molecular dynamics and the ReaxFF reactive force field. The shock compression method produces activated carbon with surface functionalities, primarily hydroxyl groups, and varying morphological properties. Two approaches, unidirectional and isotropic compression, yield distinct surface structures: the former preserves a relatively flat surface, while the latter generates corrugated features with valleys and ridges. These features significantly impact the adsorption properties of methylene blue (MB), a commonly used dye. Simulations reveal that MB molecules are highly mobile on flat surfaces, aligning with a mobile adsorption model. However, on corrugated surfaces, MB exhibits localized adsorption, with the deepest valleys effectively immobilizing the dye molecules. Additionally, the study highlights the influence of surface hydroxyl groups, which, through interactions with water molecules, prevent MB from occupying these regions. The findings underscore that traditional adsorption models may not fully capture the dynamics of MB adsorption on activated carbons with complex morphologies. These insights are critical for advancing carbon-based adsorbents in water purification applications.
本研究通过在水存在的情况下对石墨进行冲击压缩来探索功能化碳表面的形成，使用分子动力学和ReaxFF反应力场进行建模。冲击压缩法产生具有表面官能团（主要是羟基）和不同形态特性的活性炭。单向压缩和各向同性压缩这两种方法产生了不同的表面结构：前者保留了相对平坦的表面，而后者产生了带有谷和脊的波纹状特征。这些特征对常用染料亚甲基蓝（MB）的吸附性能有显著影响。模拟表明，MB分子在平坦表面上具有高度的流动性，符合移动吸附模型。然而，在波纹状表面上，MB表现出局部吸附，最深的谷有效地固定了染料分子。此外，该研究强调了表面羟基的影响，通过与水分子的相互作用，羟基阻止MB占据这些区域。研究结果强调，传统吸附模型可能无法完全捕捉MB在具有复杂形态的活性炭上的吸附动力学。这些见解对于推进基于碳的吸附剂在水净化应用中的发展至关重要。
