北京大学郭雪峰团队报道了单键水平界面离子的原位检测。相关研究成果于2024年9月12日发表在国际知名学术期刊《美国化学会杂志》。

检测固液界面上的离子状态，对于揭示界面上发生的各种化学和物理过程至关重要。

该文中，研究人员使用扫描隧道显微镜断裂结技术，检测了高电负性离子F^-和OH^-在固液界面上的吸附状态。以氨基的活性氢原子为探针，成功检测到形成的离子氢键，从而能够原位监测固液界面上的离子状态。

通过噪声功率谱密度分析和理论模拟，研究人员揭示了界面上离子氢键影响电荷输运性质的机制。此外，研究发现电场可以有效地操纵固液界面上的离子态。在高电场下，电极附近的阴离子浓度较高，形成的氢键比例大于低电场下的氢键比例。

该项对单键水平界面离子态的研究，为设计用于能量转换和环境净化的高性能材料提供了指导。

附：英文原文

Title: In Situ Detection of Interfacial Ions at the Single-Bond Level

Author: Xiao Wei, Xinyue Chang, Jie Hao, Fengyi Liu, Ping Duan, Chuancheng Jia, Xuefeng Guo

Issue&Volume: September 12, 2024

Abstract: Detecting the ionic state at the solid–liquid interface is essential to reveal the various chemical and physical processes that occur at the interface. In this study, the adsorption states of the highly electronegative ions F– and OH– at the solid–liquid interface are detected by using the scanning tunneling microscopy break junction technique. With the active hydrogen atom of the amino group as a probe, the formed ionic hydrogen bonds are successfully detected, thereby enabling in situ monitoring of the ionic state at the solid–liquid interface. Through noise power spectral density analysis and theoretical simulations, we reveal the mechanism by which ionic hydrogen bonds at the interface affect the charge transport properties. In addition, we discover that the ionic state at the solid–liquid interface can be effectively manipulated by electric fields. Under high electric fields, the concentration of the anion near the electrode is higher, and the proportion of hydrogen bonds formed is greater than that under low electric fields. This study of the interfacial ionic state at the single-bond level provides guidance for the design of high-performance materials for energy conversion and environmental purification.

DOI: 10.1021/jacs.4c06738

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c06738