Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, China.
School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China.
Sci Total Environ. 2020 Oct 15;739:139983. doi: 10.1016/j.scitotenv.2020.139983. Epub 2020 Jun 5.
A 3D pretreated peanut shell-supported graphene oxide (PPS/GO) aerogel has been facilely prepared through a brief sonication + freeze-shaping technique, avoiding the traditional application of hydrothermal method which suffered from high temperature and long reaction time as well as significant loss of oxygen-containing functional groups. It was then employed to efficient norfloxacin (NOR) removal from aqueous medium. The mechanism of sonication time on the structure and adsorption properties of as-obtained PPS/GO aerogels was emphatically discussed via combining instrumental analyses, batch adsorption experiments and density functional theory (DFT) calculations. Results showed that the 3D PPS/GO aerogel with a decrease in oxygen functional groups and an increase in sp-derived sp hybridization regions was observed as sonication time provided in excess, causing the worse removal efficiency towards NOR. The resulting PPS/GO(5:1) aerogel obtained at sonication of 2 min and GO loading content of 200 mg/(PPS)g exhibited the optimal NOR adsorption capacity (pH 6.2, 228.83 mg g). DFT calculations further identified that the sp-hybridized areas in PPS/GO aerogel had much lower adsorption energy (ΔE, -6.69 kcal/mol) towards NOR as compared with that of sp-hybridized zones (-12.45 kcal/mol). In addition, multiple interactions were involved in the adsorption of NOR by 3D PPS/GO aerogel, including electrostatic attraction, H-bonding, π-π conjugation and hydrophobic effect.
一种 3D 预处理花生壳支撑氧化石墨烯（PPS/GO）气凝胶通过简单的超声+冷冻成型技术制备，避免了传统水热法应用中存在的高温、长反应时间以及含氧官能团大量损失的问题。然后，它被用于从水溶液中高效去除诺氟沙星（NOR）。通过结合仪器分析、批量吸附实验和密度泛函理论（DFT）计算，重点讨论了超声时间对所获得的 PPS/GO 气凝胶结构和吸附性能的影响机制。结果表明，随着超声时间的增加，观察到 3D PPS/GO 气凝胶中含氧官能团减少，sp 衍生的 sp 杂化区域增加，导致 NOR 的去除效率下降。在超声 2 分钟和 GO 负载量为 200mg/（PPS）g 的条件下，得到的 PPS/GO（5:1）气凝胶对 NOR 的吸附容量最佳（pH 6.2，228.83mg g）。DFT 计算进一步表明，与 sp 杂化区（-12.45 kcal/mol）相比，PPS/GO 气凝胶中的 sp 杂化区域对 NOR 的吸附能（ΔE，-6.69 kcal/mol）要低得多。此外，3D PPS/GO 气凝胶对 NOR 的吸附涉及多种相互作用，包括静电吸引、氢键、π-π 共轭和疏水作用。
