Increased electron transfer kinetics and thermally treated graphite stability through improved tunneling paths (original) (raw)

Aging of graphite-based materials results in slower heterogeneous electron transfer (HET) kinetics and limits their conducting and catalytic performance. A thermal treatment protocol reportedly maintained a high HET kinetics of graphite by at least nine weeks. The present report investigates the consequences of such HET increases on graphite stabilities. Raman 2D peak evolution, potential windows, EIS, optical AFM, chronoamperometry and potentiodynamic polarization studies were employed to investigate electrochemical, structural and corrosion stabilities and mechanisms of the pristine and thermally treated graphite as they relate to its HET kinetics. Structure-induced electronic changes are suggested to trigger improved tunneling paths through the interfaces from the bulk layer. This tunneling improves and sustains HET kinetics by orders of magnitude in the treated graphite. Except for the graphite fibers, thermal treatment increased HET kinetics without compromises to electrochemical, structural and corrosion stabilities. In most instances, these properties improved over the pristine graphite.