Oxygen Reduction Reaction Activity of Aerosol Jet Printed Layers of Graphite and Graphene
Graphene and graphite were formulated into high concentration inks (10mg/mL). These inks were aerosol jet printed to create micron scale layers (2 – 10 microns). The catalytic activity of the aerosol jet printed electrodes was evaluated in oxygen saturated basic solution. It was found that the oxygen reduction reaction activity of the aerosol jet printed graphene electrode was ~ 5 times higher times than the activity of the same material when drop cast. Electrochemical impedance spectroscopy showed that the activity difference correlated with a large decrease in the charge transfer resistance of aerosol jet printed graphene as opposed to drop cast graphene. Further, the activity of the aerosol jet printed graphene electrode was ~ 3 times greater than the activity of the aerosol jet printed graphite. In contrast, the drop cast materials did not show a measurable difference in performance. These results indicate that aerosol jet printing is a viable way to deposit micron scale layers of graphene and related materials. In addition, the activity of the graphene electrode is strongly dependent on the deposition method, with aerosol jet deposited electrodes showing a strong performance improvement over their drop cast counterparts.