Reduction of iron phthalocyanine/ graphene oxide composites using atmospheric pressure plasma

Fuel cells have been used for fuel cell vehicles or household power sources as an energy source with a low environmental load. The development of non-platinum-based catalysts has been required in order to improve the electromotive force, the cost, and the durability of the conventional platinum-supported carbon catalysts. We focused on the iron phthalocyanine (FePc) / graphene oxide (GO) composites as an alternative catalyst because of high oxygen reduction reaction. General reduction methods to improve oxygen reduction reaction are a hydrazine reduction or thermal reduction with hydrogen gas and are harmful to the environment and human body. In this study, the FePc / GO composites was reduced by the treatment using cold atmospheric-pressure plasma (CAP) on low temperature.

FePc / GO composites of 30mg were treated using the CAP. The applied voltage with frequency of 60Hz was 17kV. H₂ gas flow rate ratio to Ar gas was 1% and the total flow rate was 2.5slm. The electrochemical properties were evaluated using a linear sweep voltammetry in acid condition.

The oxygen reduction onset potential at current density of -0.02mA/cm² was improved to be 0.7V from 0.5V by 120min CAP treatment. This result indicates that the reduction of FePc / GO composites was performed by the CAP treatment.