AVS 65th International Symposium & Exhibition
    In-situ Microscopy, Spectroscopy, and Microfluidics Focus Topic Monday Sessions
       Session MM+AS+NS+PC+SS-MoA

Paper MM+AS+NS+PC+SS-MoA10
Observation of Electric Double Layer under Graphene by Scanning Electron Microscopy

Monday, October 22, 2018, 4:20 pm, Room 202B

Session: X-ray and Electron Spectromicroscopy in Liquids and Gases & Flash Networking Session
Presenter: Hongxuan Guo, National Institute of Standards and Technology (NIST)/ University of Maryland, College Park
Authors: H.X. Guo, National Institute of Standards and Technology (NIST)/ University of Maryland, College Park
A. Yulaev, National Institute of Standards and Technology (NIST)/ University of Maryland, College Park
E. Strelcov, National Institute of Standards and Technology (NIST)/ University of Maryland, College Park
A. Tselev, CICECO and Department of Physics, University of Aveiro,Portugal
A. Kolmakov, National Institute of Standards and Technology
Correspondent: Click to Email
The formation of the electric double layer is a fundamental phenomenon occurring at electrified solid-liquid electrolyte interfaces and which has a key importance for energy devices, chemical engineering and biomedical applications. The structure and composition of electric double layer can be accessed using optical methods 1, and more recently with X-ray spectroscopy 2, 3, as well as scanning probe microscopy4.

In this presentation, we demonstrate the feasibility of in-situ scanning electron microscopy to observe the changes in electric double layer in different electrolytes upon polarization. We designed an electrochemical liquid cell with electron transparent electrode made of bilayer graphene.5,6. We monitored the changes in secondary electron yield from the graphene-liquid interface upon electrolyte polarization. We found that the normalized SEM image contrast is linear with the applied bias voltage and is related to the concentration and distribution of the ions at the interface. The analysis of SEM videos provide insight on long term kinetics of ionic moieties in electrolyte during polarization. This experimental methodology will be helpful for understanding the structure, property, and dynamics of the electric double layer at solid -electrolyte interfaces.

Reference

[1]. F. Zaera Chem. Rev. 112(2012),2920–2986

[2]. M. Favaro, B. Jeong, P. N. Ross, J. Yano, Z. Hussain, Z. Liu and E. J. Crumlin, Nature Communications 7(2016), 12695

[3]. M. A. Brown, Z. Abbas, A. Kleibert, R. G. Green, A. Goel, S. May, and T. M. Squires, Physical Review X 6(2016), 011007

[4]. J. M. Black, M. Zhu, P. Zhang, R. R. Unocic, D. Guo, M. B. Okatan, S. Dai, P. T. Cummings, S. V. Kalinin, G. Feng, and N. Balke, Scientific Reports 6 (2016), 32389

[5]. A. Yulaev, H. Guo, E. Strelcov, L. Chen, I. Vlassiouk, A Kolmakov, ACS applied materials & interfaces 9 (2017), 26492-26502

[6]. H. Guo, E. Strelcov, A. Yulaev, J. Wang, N. Appathurai, S. Urquhart, J. Vinson, S. Sahu, M. Zwolak, and A. Kolmakov, Nano Letters,17(2017), 1034–1041