Performance evaluation of graphene oxide–MnO2 nanocomposite for alkaline membrane fuel cell.

The manganese dioxide/graphene oxide (MnO2/GO) nanocomposites were prepared from hydrothermally synthesized MnO2 nanorods and graphene oxide. Electrocatalytic performance for the oxygen reduction reactions (ORR) of the fabricated MnO2/GO nanocomposites was evaluated using the rotating disk electrode (RDE) method. It is found that MnO2/GO nanocomposites deliver significantly enhanced performance compared to standalone MnO2 and GO with current density and onset potential values of 5.1 mA/cm2 and 0.93 V versus RHE, respectively. The alkaline membrane fuel cell (AMFC) characteristics were also studied. In particular, the single‐cell alkaline fuel cell stack with MnO2/GO nanocomposite as cathode loading produced a peak power density value of 82 mW/cm2. Our findings revealed great potential for MnO2/GO nanocomposites for their electrocatalytic performance and utilization in AMFC as the cathode. Namely, MnO2/GO achieved fuel cell functionalities that were comparable to the widely used commercial Pt/C. The enhanced electrochemical performance of MnO2/GO is attributed to the synergistic interaction between highly conductive GO sheets and active sites of MnO2 nanorods. The commendable performance of MnO2/GO suggests that it can be used as electrocatalysts in alkaline fuel cell applications. [ABSTRACT FROM AUTHOR]