Enhancement of the electrochemical membrane electrode assembly in proton exchange membrane fuel cells through direct microwave treatment

• We developed a new method of direct microwave irradiation treatment to the MEA.
• Improved micropore structure was achieved using microwave treatment.
• High active site at the catalyst layer was achieved using microwave treatment.
• High Pt utilization at the catalyst layers was achieved using microwave treatment.
• The microwave-irradiated MEA show superior cell performance over non-treated MEA.

Demonstrated herein is a novel and easily controllable method using direct microwave irradiation treatment to enhance the electrochemical structure in the membrane electrode assembly (MEA) of the fuel cell. Through direct microwave irradiation, it is found that the pore dimension changed to an improved micropore structure with a 1.5-fold larger surface area (from 9.68 to 15.21 m2 g−1) at the microwave power of 500 W than the rare statement, which is proportional to the mass/heat transfer properties, along with the higher interfacial site area in the electrode, for better electrochemical properties. This upgraded structure also increases the Pt catalyst utilization and reduces the electrical loss by increasing the ionic conductivity between the catalyst layer and membrane when combined with polymer electrolyte, a catalyst, and the Nafion membrane in MEA. Due to the enhancement of the MEA properties, the fuel cell performances of the microwave-irradiated MEAs show a significant improvement to 1.87 A cm−2 at 0.6 V over the conventional MEA performance of 1.47 A cm−2. Especially achieved is a 110% enhancement in the limiting current density resulting from the developed electrochemical micropore structure.