Platinum-based alloy nanoparticles are the most attractive catalysts for the oxygen reduction reaction at present, but an in-depth understanding of the relationship between their short-range structural information and catalytic performance is still lacking. Herein, we present a synthetic strategy that uses transition-metal oxide-assisted thermal diffusion. PtCo/C catalysts with localized tetragonal distortion were obtained by controlling the thermal diffusion process of transition-metal elements. This localized structural distortion induced a significant strain effect on the nanoparticle surface, which further shortened the length of the Pt–Pt bond, improved the electronic state of the Pt surface, and enhanced the performance of the catalyst. PtCo/C catalysts with special short-range structures achieved excellent mass activity (2.27 A mg_Pt⁻¹) and specific activity (3.34 A cm⁻²). In addition, the localized tetragonal distortion-induced surface compression of the Pt skin improved the stability of the catalyst. The mass activity decreased by only 13% after 30,000 cycles. Enhanced catalyst activity and excellent durability have also been demonstrated in the proton exchange membrane fuel cell configuration. This study provides valuable insights into the development of advanced Pt-based nanocatalysts and paves the way for reducing noble-metal loading and increasing the catalytic activity and catalyst stability.

中文翻译：

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Pt合金催化剂的局部四方变形提高氧还原反应效率

铂基合金纳米粒子是目前氧还原反应最有吸引力的催化剂，但对其短程结构信息与催化性能之间关系的深入了解仍缺乏。在这里，我们提出了一种使用过渡金属氧化物辅助热扩散的合成策略。通过控制过渡金属元素的热扩散过程，获得了具有局域四方畸变的PtCo/C催化剂。这种局部结构畸变对纳米粒子表面产生了显着的应变效应，进一步缩短了Pt-Pt键的长度，改善了Pt表面的电子态，增强了催化剂的性能。具有特殊短程结构的PtCo/C催化剂具有优异的质量活性（2.27 A mg _Pt ^-1）和比活性（3.34 A cm ^-2）。此外，铂皮的局部四方变形引起的表面压缩提高了催化剂的稳定性。30,000 次循环后，质量活性仅下降 13%。质子交换膜燃料电池配置也证明了增强的催化剂活性和出色的耐用性。这项研究为先进铂基纳米催化剂的开发提供了宝贵的见解，并为减少贵金属负载量、提高催化活性和催化剂稳定性铺平了道路。