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High‐temperature proton exchange membrane fuel cells (HT‐PEMFCs) are crucial in future energy systems. However, the activity and stability of the electrocatalysts are severely restricted by high temperature and phosphoric acid poisoning. Herein, PtCe alloy as oxygen reduction reaction (ORR) electrocatalyst for HT‐PEMFCs exhibits fantastic performance. Ce can increase the electronic density of Pt, weakening phosphoric acid poisoning and improving ORR activity. The optimized electronic structure can also reduce the dipole effect between Pt and O, which suppresses the irreversible oxidation of Pt. Additionally, the dramatically negative heat of formation in PtCe catalyst brings high kinetic barrier of metal diffusion and dissolution. With this electrocatalyst, the HT‐PEMFCs show a preeminent peak power of 605 mW cm−2 with 0.3 mgPt cm−2. After 30000 cycles of accelerated stability test, the peak power density only decreases by 31.6%, achieving the goal of Department of Energy in 2020 (<40% loss). [ABSTRACT FROM AUTHOR]

The durability degradation during stack‐operating conditions seriously deteriorates the lifetime and performance of the fuel cell. To alleviate the rapid potential rise and performance degradation, an anode design is proposed to match the working temperature of high‐temperature proton exchange membrane fuel cells (HT‐PEMFCs) with the release temperature of hydrogen from palladium. The result is significantly enhanced hydrogen oxidation reaction (HOR) activity of Pd and superior performance of the Pd anode. Furthermore, Pd as hydrogen buffer and oxygen absorbent layer in the anode can provide additional in situ hydrogen and absorb infiltrated oxygen during local fuel starvation to maintain HOR and suppress reverse‐current degradation. Compared with the traditional Pt/C anode, the Pd/C also greatly improved HT‐PEMFCs durability during start‐up/shut‐down and current mutation. The storage/release of hydrogen provides innovative guidance for improving the durability of PEMFCs. [ABSTRACT FROM AUTHOR]