Abstract

We report Raman spectra and infrared (IR) imaging collected during the intercalation–deintercalation half cycles in a multilayer graphene (MLG) device (∼100 layers) operating at 0.2–10 Hz. The device consists of a MLG/alumina membrane/copper stack, in which the alumina membrane is filled with ionic liquid [DEME][TFSI], forming an electrochemical cell. Upon the application of a positive voltage, the TFSI– anions intercalate into the interstitial spaces in the MLG. The incident laser light is modulated using an optical chopper wheel that is synchronized with (and delayed with respect to) a 0.2–10 Hz alternating current (AC) voltage signal. Raman spectra taken just 200 ms apart show the emergence and disappearance of the intercalated G band mode at around 1610 cm–1. By integration of over hundreds of cycles, a significant Raman signal can be obtained. The intercalation/deintercalation is also monitored with …

Date

August 8, 2023

Authors

Zhi Cai, Haley Weinstein, Indu Aravind, Ruoxi Li, Sizhe Weng, Boxin Zhang, Jonathan L Habif, Stephen B Cronin

Journal

The Journal of Physical Chemistry Letters

Volume

14

Issue

32

Pages

7223-7228

Publisher

American Chemical Society