Graphene/carbon structured catalyst layer to enhance the performance and durability of the high-temperature proton exchange membrane fuel cells

In this study, nitrogen doped electrochemically exfoliated reduced graphene oxide and carbon black supported platinum (Pt/NrEGO₂-CB₃) has been prepared to enhance the performance and durability of high-temperature PEMFCs with lower Pt loading. On the one hand, Pt/NrEGO₂-CB₃ with the strong interaction between the Pt and nitrogen (N) prevent agglomeration of Pt particles and Pt particles is 5.46 ± 1.46 nm, which is smaller than that of 6.78 ± 1.34 nm in Pt/C. Meanwhile, ECSA of Pt/NrEGO₂-CB₃ decrease 13.65% after AST, which is much lower than that of 97.99% in Pt/C. On the other hand, the NrEGO flakes in MEA_ac act as a barrier to mitigate phosphoric acid redistribution, which improves the formation of triple-phase boundaries (TPBs) and gives stable operation of the MEA_ac with a lower decay rate of 0.02 mV h⁻¹ within 100 h. After steady-state operation, the maximum power density of Pt/NrEGO₂-CB₃ (0.411 W cm⁻²) is three times higher than that of conventional Pt/C (0.134 W cm⁻²) in high-temperature PEMFCs. After AST, the mass transfer resistance of Pt/NrEGO₂-CB₃ electrode (0.560 Ω cm²) is lower than that in Pt/C (0.728 Ω cm²).