PdO-CeO₂ nanocomposites have many potential (electro) catalytic applications but are routinely synthesized at a high temperature. Herein, we report low-temperature synthesis of uniform PdO nanoparticles decorated by nearly amorphous CeO₂ supported on carbon (PdO-CeO₂/C). Unlike previous chemical oxidation of Pd to PdO at 500°C, Pd is electrochemically oxidized to PdO paired with CeO₂/CeO_2-x at 250 C. To the best of our knowledge, the synthesis of PdO at such a low temperature has not been reported before this study. Compared with commercial Pt/C, PdO-CeO₂/C exhibits an excellent oxygen reduction reaction (ORR) activity in alkaline media in terms of a remarkable mass activity (MA) of 1103 mA mg_Pd⁻¹ (at 0.9 V vs. reversible hydrogen electrode), which is 5.9 times of that of commercial Pt/C. Density functional theory suggests that the high ORR activity may arise from an appropriate oxygen adsorption strength at the interface of PdO-CeO₂. In addition, after 4000 cycles of accelerated durability tests, the MA of the PdO-CeO₂/C only decreases 13.4% superior to commercial Pt/C with a loss of 55.5%. The significantly enhanced durability should be correlated to the strong interfacial interaction between PdO and CeO₂, which well anchors PdO and suppresses the migration of PdO to form large aggregates.

PdO-CeO ₂纳米复合材料具有许多潜在的（电）催化应用，但通常在高温下合成。在本文中，我们报道了由负载在碳上的几乎无定形的CeO ₂（PdO-CeO ₂ / C）装饰的均匀PdO纳米颗粒的低温合成。与以前在500°C下将Pd化学氧化为PdO不同，Pd在250 °C被电化学氧化为与CeO ₂ / CeO _2-x配对的PdO 。据我们所知，在如此低的温度下合成PdO并没有这项研究之前已有报道。与商用Pt / C相比，PdO-CeO ₂/ C在碱性介质中表现出出色的氧还原反应（ORR）活性，其显着的质量活度（MA）为1103 mA mg _Pd ^-1（在0.9 V下相对于可逆氢电极），是其的5.9倍。商业Pt / C。密度泛函理论认为，高ORR活性可能是由于PdO-CeO ₂界面处的适当氧吸附强度引起的。此外，经过4000次加速耐久性测试，PdO-CeO ₂ / C的MA仅比商用Pt / C降低13.4％，损失为55.5％。显着增强的耐久性应与PdO和CeO ₂之间的强界面相互作用有关，它很好地固定了PdO，并抑制了PdO的迁移以形成大的聚集体。