Li Xiaoqun, Brigiano Flavio S, Pezzotti Simone, Liu Xinyi, Chen Wanlin, Chen Huiling, Li Ying, Li Hui, Lin Xin, Zheng Wenqi, Wang Yuchong, Shen Yue Ron, Gaigeot Marie-Pierre, Liu Wei-Tao
Physics Department, State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures, Ministry of Education, Fudan University, Shanghai, China.
Department of Chemistry, The Hong Kong University of Science and Technology, Hong Kong SAR, China.
Nat Chem. 2025 Feb;17(2):198-203. doi: 10.1038/s41557-024-01658-y. Epub 2024 Oct 14.
Oxide-water interfaces host a wide range of important reactions in nature and modern industrial applications; however, accurate knowledge about these interfaces is still lacking at the molecular level owing to difficulties in accessing buried oxide surfaces. Here we report an experimental scheme enabling in situ sum-frequency vibrational spectroscopy of oxide surfaces in liquid water. Application to the silica-water interface revealed the emergence of unexpected surface reaction pathways with water. With ab initio molecular dynamics and metadynamics simulations, we uncovered a surface reconstruction, triggered by deprotonation of surface hydroxylated groups, that led to unconventional five-coordinated silicon species. The results help demystify the multimodal chemistry of aqueous silica discovered decades ago, bringing in fresh information that modifies the current understanding. Our study will provide new opportunities for future in-depth physical and chemical characterizations of other oxide-water interfaces.
氧化物 - 水界面在自然界和现代工业应用中承载着广泛的重要反应；然而，由于难以接触到埋藏的氧化物表面，在分子水平上对这些界面仍缺乏准确的认识。在此，我们报告了一种实验方案，能够对液态水中的氧化物表面进行原位和频振动光谱分析。应用于二氧化硅 - 水界面揭示了与水发生的意外表面反应途径。通过从头算分子动力学和元动力学模拟，我们发现了由表面羟基化基团去质子化引发的表面重构，这导致了非常规的五配位硅物种。这些结果有助于揭开几十年前发现的含水二氧化硅多模态化学的神秘面纱，带来修改当前认识的新信息。我们的研究将为未来深入物理和化学表征其他氧化物 - 水界面提供新机会。
