Reactive metal–support interaction of In₂O₃/crystalline carbon hybrid support for highly durable and efficient oxygen reduction reaction electrocatalyst

Proton exchange membrane fuel cells (PEMFCs) have demonstrated significant promise in the context of achieving net-zero carbon emissions. However, the long-term stabilities and high efficiencies of membrane electrode assemblies (MEAs) must be addressed to promote the commercialization of such fuel cells. Herein, a highly durable electrocatalyst is presented for use in the oxygen reduction reaction (ORR). This electrocatalyst is based on a crystalline carbon (CC) support that is uniformly decorated with In₂O₃ via atomic layer deposition. In addition, it was confirmed that reactive metal–support interaction between the Pt catalyst and the In₂O₃ interfacial support layer enhanced the catalytic activity and durability of the material. Consequently, the mass activity of the synthesized Pt/In₂O₃/CC was determined to be 0.512 A/mg_Pt, which is three times higher than that of commercial Pt/C. Electrochemical durability tests revealed the superior long-term stability of the Pt/In₂O₃/CC catalyst compared to that of Pt/C. The support durability test of the MEA also showed no degradation in the power density, even after a startup/shutdown test over >5000 cycles. The notable stability enhancement of the catalyst during cell operation was attributed to the synergetic effect of the corrosion-resistant CC and reactive metal–support interactions between Pt and In₂O₃. This approach offers a viable pathway for the development of highly durable ORR catalysts for the commercialization of PEMFCs, particularly in the context of heavy-duty vehicle applications.