Legerstee W J, Boekel M, Boonstra S, Kelder E M
Storage of Electrochemical Energy, Radiation Science and Technology, Applied Sciences, Delft University of Technology, Delft, Netherlands.
Automotive Engineering, Engineering and Applied Sciences, Rotterdam University of Applied Sciences, Rotterdam, Netherlands.
Front Chem. 2021 Apr 15;9:505876. doi: 10.3389/fchem.2021.505876. eCollection 2021.
An Atomic Force Microscope (AFM) is combined with a special designed glovebox system and coupled to a Galvanostat/Potentiostat to allow measurements on electrochemical properties for battery research. An open cell design with electrical contacts makes it possible to reach the electrode surface with the cantilever so as to perform measurements during battery operation. A combined AFM-Scanning Electro-Chemical Microscopy (AFM-SECM) approach makes it possible to simultaneously obtain topological information and electrochemical activity. Several methods have been explored to provide the probe tip with an amount of lithium so that it can be used as an active element in a measurement. The "wet methods" that use liquid electrolyte appear to have significant drawbacks compared to dry methods, in which no electrolyte is used. Two dry methods were found to be best applicable, with one method applying metallic lithium to the tip and the second method forming an alloy with the silicon of the tip. The amount of lithium applied to the tip was measured by determining the shift of the resonance frequency which makes it possible to follow the lithiation process. A FEM-based probe model has been used to simulate this shift due to mass change. The AFM-Galvanostat/Potentiostat set-up is used to perform electrochemical measurements. Initial measurements with lithiated probes show that we are able to follow ion currents between tip and sample and perform an electrochemical impedance analysis in absence of an interfering Redox-probe. The active probe method developed in this way can be extended to techniques in which AFM measurements can be combined with mapping electrochemical processes with a spatial resolution.
原子力显微镜（AFM）与特殊设计的手套箱系统相结合，并与恒电流仪/恒电位仪耦合，以进行电池研究中的电化学性能测量。具有电接触的开放式电池设计使得悬臂能够接触到电极表面，从而在电池运行期间进行测量。原子力显微镜-扫描电化学显微镜（AFM-SECM）相结合的方法使得同时获取拓扑信息和电化学活性成为可能。已经探索了几种方法来为探针尖端提供一定量的锂，以便它可以在测量中用作活性元素。与不使用电解质的干法相比，使用液体电解质的“湿法”似乎有明显的缺点。发现两种干法最适用，一种方法是将金属锂施加到尖端，另一种方法是使尖端的硅形成合金。通过确定共振频率的偏移来测量施加到尖端的锂的量，这使得跟踪锂化过程成为可能。基于有限元法的探针模型已被用于模拟由于质量变化引起的这种偏移。AFM-恒电流仪/恒电位仪装置用于进行电化学测量。用锂化探针进行的初始测量表明，我们能够跟踪尖端和样品之间的离子电流，并在没有干扰性氧化还原探针的情况下进行电化学阻抗分析。以这种方式开发的活性探针方法可以扩展到AFM测量可以与具有空间分辨率的电化学过程映射相结合的技术。
