(a)
Voltage profile showing the ex-situ FT-IR spectra sampling
points. (b) Ex-situ FT-IR spectra of electrodes in different states
of charge: pristine electrode (red), discharged to 0.9 V (green),
discharged to 0.25 V (blue), and recharged to 1.6 V (brown). (c) Zoomed-in
ex-situ FT-IR insert of electrodes in different states of charge.
(d) CV curves of OTQC measured by a three-electrode system at 10 mV
s–1 in 3 M ZnSO4 (pH = 3.7) (red), 3
M ZnSO4 + H2SO4 (pH = 1) (blue),
and H2SO4 (pH = 1) green. (e) Galvanostatic
charge/discharge curves of OTQC in different electrolytes including
1 M Zn(TFSI)2 in G2 (black, 5th cycle), 2.2 M Zn(OTf)2 in 70% PEG (red, 2nd cycle), and 3 M ZnSO4 (blue,
2nd cycle). (f) Ex-situ UV–vis spectrum of electrodes submerged
in 3 M ZnSO4 at different states of charge: discharged
to 0.9 V (green), discharged to 0.25 V (blue), and charged to 1.6
V (brown).