Sakr Mahmoud A S, Saad Mohamed A, Saroka Vasil A, Abdelsalam Hazem, Zhang Qinfang
Center of Basic Science (CBS), Misr University for Science and Technology (MUST), 6th, October City, Egypt.
Department of Physics, University of Rome Tor Vergata and INFN, Via della Ricerca Scientifica 1, Roma, 00133, Italy.
J Fluoresc. 2024 Mar;34(2):945-960. doi: 10.1007/s10895-023-03334-9. Epub 2023 Jul 12.
In this study, we investigated the reactivity of γ-graphyne (Gp) and its derivatives, Gp-CH, Gp-COOH, Gp-CN, Gp-NO, and Gp-SOH, for the removal of toxic heavy metal ions (Hg, Pb, and Cd) from wastewater. From the analysis of the optimized structures, it was observed that all the compounds exhibited planar geometry. The dihedral angles (C9-C2-C1-C6 and C9-C2-C1-C6) were approximately 180.00°, indicating planarity in all molecular arrangements. To understand the electronic properties of the compounds, the HOMO (E) and LUMO (E) energies were calculated, and their energy gaps (E) were determined. The E and E values ranged between - 6.502 and - 8.192 eV and - 1.864 and - 3.773 eV, respectively, for all the compounds. Comparing the E values, Gp-NO exhibited the most stable HOMO, while Gp-CH had the least stable structure. In terms of E values, Gp-NO had the most stable LUMO, while Gp-CH was the least stable. The E values followed the order: Gp-NO < Gp-COOH < Gp-CN < Gp-SOH < Gp-CH3 < Gp, with Gp-NO (4.41 eV) having the smallest energy gap. The density of states (DOS) analysis showed that the shape and functional group modifications affected the energy levels. Functionalization with electron-withdrawing (CN, NO, COOH, SOH) or electron-donating (CH) groups reduced the energy gap. To specifically target the removal of heavy metal ions, the Gp-NO ligand was selected for its high binding energy. Complexes of Gp-NO-Cd, Gp-NO-Hg, and Gp-NO-Pb were optimized, and their properties were analyzed. The complexes were found to be planar, with metal-ligand bond distances within the range of 2.092→3.442 Å. The Gp-NO-Pb complex exhibited the shortest bond length, indicating a stronger interaction due to the smaller size of Pb. The computed adsorption energy values (E) indicated the stability of the complexes, with values ranging from - 0.035 to -4.199 eV. Non-covalent interaction (NCI) analysis was employed to investigate intermolecular interactions in Gp-NO complexes. The analysis revealed distinct patterns of attractive and repulsive interactions, providing valuable insights into the binding preferences and steric effects of heavy metals.
在本研究中，我们研究了γ-石墨炔（Gp）及其衍生物Gp-CH、Gp-COOH、Gp-CN、Gp-NO和Gp-SOH从废水中去除有毒重金属离子（Hg、Pb和Cd）的反应活性。通过对优化结构的分析，观察到所有化合物均呈现平面几何形状。二面角（C9-C2-C1-C6和C9-C2-C1-C6）约为180.00°，表明所有分子排列均具有平面性。为了解这些化合物的电子性质，计算了最高占据分子轨道（HOMO）（E）和最低未占分子轨道（LUMO）（E）的能量，并确定了它们的能隙（E）。所有化合物的E和E值分别在-6.502至-8.192 eV和-1.864至-3.773 eV之间。比较E值，Gp-NO表现出最稳定的HOMO，而Gp-CH的结构最不稳定。就E值而言，Gp-NO具有最稳定的LUMO，而Gp-CH最不稳定。E值的顺序为：Gp-NO＜Gp-COOH＜Gp-CN＜Gp-SOH＜Gp-CH3＜Gp，其中Gp-NO（4.41 eV）的能隙最小。态密度（DOS）分析表明，形状和官能团修饰影响了能级。用吸电子（CN、NO、COOH、SOH）或供电子（CH）基团进行功能化降低了能隙。为了专门针对重金属离子的去除，选择了具有高结合能的Gp-NO配体。优化了Gp-NO-Cd、Gp-NO-Hg和Gp-NO-Pb的配合物，并分析了它们的性质。发现这些配合物是平面的，金属-配体键长在2.092→3.442 Å范围内。Gp-NO-Pb配合物的键长最短，表明由于Pb的尺寸较小，相互作用更强。计算得到的吸附能值（E）表明了配合物的稳定性，其值在-0.035至-4.199 eV之间。采用非共价相互作用（NCI）分析来研究Gp-NO配合物中的分子间相互作用。分析揭示了吸引和排斥相互作用的不同模式，为重金属的结合偏好和空间效应提供了有价值的见解。
