College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China.
Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China.
Environ Res. 2020 Aug;187:109656. doi: 10.1016/j.envres.2020.109656. Epub 2020 May 19.
This study compared the effects of five types of inorganic nanoparticles (INPs) on the 17β-estradiol (E2) adsorption to graphene oxide (GO). The results showed that INPs increased the equilibrium time for the adsorption of E2 to GO. Higher Brunauer-Emmett-Teller (BET) surface area of INPs resulted in lower diffusion rate of E2, and thus the adsorption rate constant (k) calculated from pseudo-second-order kinetic model negatively correlated with the BET surface area of INPs (p = 0.037). In addition, INPs decreased the adsorption amount of E2 to GO, and the inhibition effects declined in the order of AlO > ZnO > TiO > SiO > FeO. This is determined by the interactions between GO and INPs. The positively charged ZnO and AlO strongly heteroaggregate with GO via electrostatic attraction, and then significantly inhibited E2 adsorption to GO. In contrast, the homoaggregation of GO was superior to its heteroaggregation with negatively charged SiO and TiO, and then lower inhibition of E2 adsorption to GO was induced. FeO with less negative charge (-8.48 mV) led to the lowest inhibition effect on E2 adsorption to GO because of its preferable homoaggregation. The results were further confirmed by Derjaguin-Landau-Verwey-Overbeek calculation, transmission electron microscopy, and sedimentation experiments. This study revealed how the properties of INPs influence their effects on the adsorption of E2 by GO, and the findings are critical to understand the behavior and fate of GO and pollutants in natural aquatic environment.
本研究比较了五种类型的无机纳米粒子（INPs）对 17β-雌二醇（E2）在氧化石墨烯（GO）上吸附的影响。结果表明，INPs 增加了 E2 向 GO 吸附的平衡时间。INPs 的比表面积越高，E2 的扩散速率越低，因此从拟二级动力学模型计算得到的吸附速率常数（k）与 INPs 的比表面积呈负相关（p=0.037）。此外，INPs 降低了 E2 向 GO 的吸附量，其抑制效果的顺序为 AlO>ZnO>TiO>SiO>FeO。这是由 GO 和 INPs 之间的相互作用决定的。带正电荷的 ZnO 和 AlO 通过静电吸引与 GO 强烈异质聚集，从而显著抑制 E2 向 GO 的吸附。相比之下，GO 的同聚作用优于其与带负电荷的 SiO 和 TiO 的异聚作用，从而导致 E2 向 GO 的吸附抑制作用降低。带负电荷较少（-8.48 mV）的 FeO 由于其同聚作用更优，导致对 E2 向 GO 的吸附抑制作用最低。这些结果通过德加古因-兰德福-韦尔比克计算、透射电子显微镜和沉降实验进一步得到证实。本研究揭示了 INPs 的性质如何影响它们对 E2 在 GO 上吸附的影响，这些发现对于理解 GO 和污染物在自然水环境中的行为和归宿具有重要意义。
