Date of download: 12/21/2017 Copyright © ASME. All rights reserved. From: Activated Charcoal Modified Graphite Felts Using for Positive Electrodes of Vanadium Redox Flow Battery J. Electrochem. En. Conv. Stor.. 2017;14(4):041004-041004-6. doi:10.1115/1.4037532 Figure Legend: Scanning electron microscope and X-ray photoelectron spectroscopy (XPS) of experimental specimens: (a) SEM of the graphite felt before charging–discharging cycle, (b) SEM of the composite electrode before charging–discharging cycle, (c) SEM of the composite electrode after 15 charging–discharging cycles, and (d) XPS spectra of the GF and composite electrode before charging–discharging cycle