Specifically, the k 0, gra of [Ru(NH 3 ) 6 ] 3+ reduction averaged over all the devices was (9.5 ± 2.0) × 10 -2 cm s -1 , which is 3-4 orders of magnitude higher than reported previously, and close to value observed for laser-activated graphite. This indicates that mild oxidation introduces sp 3 disorder in the graphitic lattice and leads to an increase in the density of electronic states (DOS) near the E F of unbiased graphite (E F 0 ), which lies within 0.05 eV of E Ru 0' . We recognize that such effects render our analysis semi-quantitative, and as such, our main aim is to expose qualitative trends, rather than to obtain absolute values of electrochemical quantities. The evolution of the voltammetric background with N in the pure supporting electrolyte is detailed in Supporting Fig.