To further confirm anthraquinone was chemisorbed to CMK-3, control experiments were carried out. When the reaction was carried out without the addition of the TBN radical initiator, the resulting electrode material showed a cyclic voltammogram very similar to u-CMK-3, with no obvious Faradaic contributions from anthraquinone observed, suggesting that physisorbed anthraquinone and 2-AAQ is removed during the washing steps of the synthesis (Figure .1). Similarly, when u-CMK-3 was mixed with dissolved anthraquinone during the electrode film-making process, clear redox peaks were again not observed (Figure .1). In summary, the grafting of anthraquinone onto the carbon surface was confirmed using a range of characterization techniques and control experiments, with the amount of electrochemically accessible anthraquinone on the surface estimated with a lower limit of 9 wt.%.