Transforming the Pt–M alloy into an ordered intermetallic is an effective strategy to improve the electrocatalytic activity and stability toward the oxygen reduction reaction (ORR). However, the synthesis of nanosized intermetallics remains challenging. Herein, we report an efficient ORR electrocatalyst, consisting of a monodisperse nanosized PtCu intermetallic on hollow mesoporous carbon spheres (HMCS). As predicted by theoretical calculations, PtCu intermetallics exhibit beneficial electronic structure, with a low theoretical overpotential of 0.33 V and enhanced Cu stability. Resulting from the multiscale modulation of catalyst structure, the O-PtCu/HMCS catalyst delivers a high mass activity of 2.73 A cm^–2_Pt at 0.9 V and remarkable stability. Identical location transmission electron microscopy (IL-TEM) investigations demonstrate that the rate of carbon corrosion is alleviated on HMCS, which contributes to the long-term durability. This work provides a promising design strategy for an ORR electrocatalyst, and the IL-TEM investigations offer new perspectives for the performance enhancement mechanism.

中文翻译：

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有序 PtCu 金属间电催化剂的多尺度调控，用于高度耐用的氧还原反应

将 Pt-M 合金转化为有序金属间化合物是提高氧还原反应（ORR）电催化活性和稳定性的有效策略。然而，纳米金属间化合物的合成仍然具有挑战性。在此，我们报道了一种高效的ORR电催化剂，由空心介孔碳球（HMCS）上的单分散纳米尺寸PtCu金属间化合物组成。正如理论计算预测的那样，PtCu 金属间化合物表现出有益的电子结构，具有 0.33 V 的低理论过电势和增强的 Cu 稳定性。由于催化剂结构的多尺度调节，O-PtCu/HMCS 催化剂在 0.9 V 下具有 2.73 A cm ^–2 _Pt的高质量活性和卓越的稳定性。同位置透射电子显微镜 (IL-TEM) 研究表明，HMCS 的碳腐蚀速率有所减轻，这有助于长期耐用性。这项工作为 ORR 电催化剂提供了一种有前途的设计策略，并且 IL-TEM 研究为性能增强机制提供了新的视角。