in-Situ Electrochemical-AFM and CV Measurement Study on the Nucleation and Growth in Reduced Graphene Oxide Electrode Contacts

Tuesday, 30 May 2017
Grand Ballroom (Hilton New Orleans Riverside)
S. G. Pyo (School of Integrative Engineering, Chung Ang University)
Electrochemical atomic force microscopy (EC-AFM) is a composite electrochemical analysis method. A lot of researches have been done on this, and it has been applied in many fields. EC-AFM was composed of EC-Cell, electrochemical analysis system, AFM and so on. For electrochemical analysis system and AFM to be analyzed at the same time, EC-Cell with a suitable structure is required. In this study, we made an electrochemical system in AFM with CV measurement system for in-situ observation of the elctrochemical reaction. Based on the developed EC-Cell, EC-AFM experiment system which was developed by constructing EC-AFM analysis system and numerical analysis method were proposed and tested and studied. First, we confirmed the EC-AFM analysis procedure and analysis method developed by observing copper electrochemical corrosion process. Second, electrochemical reduction characteristics of graphene oxide were studied using electrochemical analysis. An electrochemical atomic force microscope (EC-AFM) was used to study the reaction of wet electrode in various electrolyte, when the reaction corresponding to what occurs at the electrode of an electrode deposition. We observed wet plated solar electrode process during cyclic-voltammetry (CV) measurement with atomic force microscopy, and then were obtained useful continuous in situ images of the surface morphology. These AFM images dynamically showed the surface morphology change during the electro deposition. It was confirmed that initial nucleation of electrode crystals occurs after supersaturation, and that the slow dissolving on CV. AFM images of the electrode crystal morphology were compared with those in a different potential sweeping rate and electrolyte concentration at CV. We also compared the difference in AFM images and SEM images that were observed on the same electrode sample. Finally, we investigated the copper electrochemical deposition process in reduced graphene oxide using EC-AFM and observed the copper film formation process on reduced graphene oxide surface. As a result, the EC-AFM analysis system was constructed and tested, and the electrochemical characteristics on the reduce graphene oxide surface were observed.