Ionic Liquid Electrochemistry 离子液体电化学

Ionic liquid Electrochemistry

Ionic liquid is a new class of green solvent in chemical research, and has attracted enormous attentions of electrochemists. However, research in and understanding of electrochemical behavior of ionic liquid, especially the electrelectrode-ionic liquid interface, is still in the infant stage. We are studying the interfacial structure of imidazolium-based ionic liquids/single crystalline electrodes by using electrochemical method and electrochemical scanning probe microscope (EC-STM). In addition, in collaboration with Prof. Zhong-Qun Tian’s team, we also employ Raman spectroscopy to obtain chemical information of the interface.

We study the differential capacitance behavior and PZCs of imidazolium-based ionic liquids with side-chain length in Au(111) and Au(100) by electrochemical impedance spectroscopy (EIS) and immersion technique. We observed the ordered adsorption structures of anions and cations in these systems by EC-STM. AFM force curves have also been employed to understand the layering distribution of the solvent ions near the surface. Furthermore, scanning tunnel spectroscopy (STS) has been used to measure the tunneling potential barrier close to the surface. Also we are carrying Raman spectroscopic investigation of the interface using SHINERS (shell isolated nanoparticles enhanced Raman spectroscopy) technique. Now we have initiated investigations of kinetics at ionic liquid- single crystal electrode interfaces.

Our interests in ionic liquid electrochemistry also include electrodeposition of metals such as Fe, Co and Ni, semi-metals such as Sb and Bi, as well as elemental semiconductors of Ge on single crystalline Au and Pt by EC-STM. Electrodeposition processes are investigated in the presence of magnetic field and with light irradiation. These investigations in ionic liquids provide basis for research of other directions in our group such as molecular electronics.

离子液体电化学

作为一种有潜力的新型绿色溶剂，离子液体受到极大关注。我们组采用传统电化学方法、电化学扫描探针技术（EC-STM）对咪唑类离子液体/单晶界面的结构进行了研究， 并与田中群教授研究团队合作，运用拉曼光谱研究离子液体界面进行研究。

我们运用电化学阻抗谱法测量了不同链长的咪唑类离子液体/Au(111)、Au(100)体系的微分电容曲线和零电荷电位等宏观界面信息。 我们运用EC-STM观察离子液体阴阳离子在各单晶表面的有序吸附结构；同时，我们采用原子力显微镜（AFM）力曲线研究了各体系界面离子层状分布情况， 并用扫描隧道谱（STS）研究了近表面的隧穿势垒随距离的变化。 此外，我们还利用壳层隔离纳米粒子增强拉曼光谱（SHINERS）探测不同电位下各体系吸附离子的取向。我们还将开展不同温度下氧化还原物种在离子液体/单晶界面电化学反应动力学的研究.

我们在离子液体电化学的研究兴趣还包括用EC-STM研究金属（Fe, Co Ni）、半金属(Sb, Bi)和元素半导体（Ge）的电沉积，并进一步辅以磁场和激光加以诱导。离子液体中的电沉积我组其它方向（如分子电子学）的开展奠定了基础。