State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Langmuir. 2012 Oct 16;28(41):14588-97. doi: 10.1021/la303413j. Epub 2012 Oct 4.
Insights from molecular-level mechanisms of catechol adsorption on goethite can further our understanding of the fate and transport of hydroxyaromatic compounds in the environment. The motivation for our study is to explore the dynamic adsorption process of catechol at the goethite/aqueous interface on the molecular scale. Multiple complementary techniques including macroscopic adsorption experiments, flow-cell ATR-FTIR measurement, 2D IR correlation analysis, and quantum chemical calculations were used to study the adsorption mechanisms. Our results show that the adsorption of catechol was elevated at high pH but was not affected by ionic strength because of the formation of inner-sphere complexes. Catechol adsorbed on goethite in mononuclear monodentate and binuclear bidentate configurations in the pH range of 5 to 9. Partial mononuclear monodentate structures could be converted to binuclear bidentate complexes under basic conditions and with increasing surface coverage.
从儿茶酚在针铁矿上吸附的分子水平机制中可以获得的认识，可以进一步帮助我们了解环境中羟基芳香族化合物的归宿和迁移。我们研究的动机是探索儿茶酚在针铁矿/水界面上的动态吸附过程。采用多种互补技术，包括宏观吸附实验、流动池 ATR-FTIR 测量、二维红外相关分析和量子化学计算，来研究吸附机制。我们的结果表明，儿茶酚在高 pH 值下的吸附增加，但不受离子强度的影响，因为形成了内圈配合物。儿茶酚在 pH 值为 5 到 9 的范围内以单核单齿和双核双齿的形式吸附在针铁矿上。在碱性条件下和表面覆盖度增加时，部分单核单齿结构可以转化为双核双齿配合物。
