Abstract A systematic theoretical study using the density functional theory was performed to provide molecular-level understanding on the adsorption of hydrogen sulfide (H 2 S) on activated carbon. Both zigzag and armchair edge sites of benzene ring models were considered as the possible active sites. The results indicate that the adsorption of H 2 S molecule on activated carbon is highly thermally favorable. The adsorption energies of H 2 S on zigzag and armchair edges are − 664.9 and − 349.6 kJ/mol, respectively. Activated carbon plays double role, not only facilitates the dissociation of H 2 S molecule but also offers active sites for H 2 S adsorption. The dissociative adsorption and evolution of H 2 S lead to the formations of C S, C S C and C SH, which is in agreement with experimental data. The shape of the local active site has a strong effect on H 2 S adsorption. The atomic charge of zigzag edge sites is more negative than that of armchair edge sites. Thus, the zigzag edge sites provide stronger force to attract H 2 S than the armchair edge sites. Direct adsorption of H 2 S leads to the formations of C S or C SH on activated carbon surface, followed by their evolution into C S C. These sulfur species including C S, C S C and C SH are stable on activated carbon.

中文翻译：

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活性炭吸附硫化氢机理的密度泛函研究

摘要 使用密度泛函理论进行了系统的理论研究，以提供对硫化氢 (H 2 S) 吸附在活性炭上的分子水平的理解。苯环模型的锯齿形和扶手椅边缘位点都被认为是可能的活性位点。结果表明，H 2 S 分子在活性炭上的吸附是高度热有利的。H 2 S 在锯齿形边缘和扶手椅边缘的吸附能分别为 - 664.9 和 - 349.6 kJ/mol。活性炭具有双重作用，不仅有利于H 2 S 分子的解离，而且还为H 2 S 的吸附提供了活性位点。H 2 S 的解离吸附和演化导致形成 CS、CSC 和 C SH，这与实验数据一致。局部活性位点的形状对H 2 S 吸附有很强的影响。锯齿形边缘站点的原子电荷比扶手椅边缘站点的原子电荷更负。因此，锯齿形边缘部位比扶手椅边缘部位提供更强的力来吸引H 2 S。H 2 S 的直接吸附导致在活性炭表面上形成 CS 或 C SH，然后它们演变成 CS C。这些硫物质包括 CS、CSC 和 C SH 在活性炭上是稳定的。