For footnotes d and e: working electrode: glassy carbon; reference electrode: Ag/Ag
þ
; counter
electrode: Pt; scan rate: 100 mV/s; calibrated with ferrocene/ferrocenium (Fc/Fc
þ
) as an internal reference and converted to NHE by addition of 630
mV.28 fEox* = Eox - E0-0.