Facile electrochemical fabrication of<scp>high‐performance</scp>graphene quantum<scp>dots‐supported Mn₃O₄</scp>/Ag hybrid catalyst for oxygen reduction reaction in alkaline media

In this study, a novel electrocatalyst based on graphene quantum dots (GQDs)-supported manganese oxide (Mn3O4) and silver (Ag) (denoted as GQDs/Mn3O4/Ag) is fabricated through the electrodeposition method, and its performance is examined toward oxygen reduction reaction (ORR). Electrochemical investigations reveal that the ORR mechanism on the fabricated catalyst forward through a four-electron transfer pathway which is identified as that of the 20% Pt/C. The prepared GQDs/Mn3O4/Ag-carbon paper (CP) presents comparable ORR performance to 20% Pt/C. It exhibits superior durability during the operation time even greater than 20% Pt/C. GQDs/Mn3O4/Ag-CP retains 94.4% of its activity after 10 000 s operation time which is much better than that of 20% Pt/C (84.7%). In addition, the better performance of GQDs/Mn3O4/Ag-CP (I: −5.63 mA.cm−2) in comparison with Mn3O4/Ag-CP (I: −4.74 mA.cm−2), GQDs/Mn3O4-CP (I: −4.63 mA.cm−2), GQDs/Ag-CP (I: −3.51 mA.cm−2), and GQDs-CP (I: −2.87 mA.cm−2) indicates that the constructed electrocatalyst with unique properties facilities the ORR kinetics.

Hali tarjima qilinmagan