摘要
PtFe/C 催化剂被列在后面由的受精和高温度的减小综合了酸沥滤。X 光检查衍射, X 光检查光电子光谱学和在边光谱学描述附近原子的 X 光检查揭示那磅 < 潜水艇 class= “ a-plus-plus ” > 3 </sub > Fe 合金形成发生在高温度的减小和那不稳定的 Fe 种期间被溶解进酸溶液。在到表面并且强壮的 O-Fe 结合的从核心区域的 Fe 集中的差别可以驾驶 Fe 的外面的散开到高度弄皱的磅骨骼,并且高度结果驱散表面 FeO <潜水艇class=“ a-plus-plus ”> x </sub>在酸的媒介是稳定的,导致磅的构造<潜水艇class=“ a-plus-plus ”> 3 </sub > Fe@Pt-FeO <潜水艇class=“ a-plus-plus ”> x </sub>建筑学。是准备了 PtFe/C 催化剂与 Pt/C 催化剂相比为氧减小反应表明一项更高的活动和可比较的耐久性,它可能在 PtFe/C 催化剂由于表面和表面下的 Fe 种类的合作效果。
A PtFe/C catalyst has been synthesized by impregnation and high-temperature reduction followed by acid-leaching. X-ray diffraction, X-ray photoelectron spectroscopy and X-ray atomic near edge spectroscopy characterization reveal that PtgFe alloy formation occurs during high-temperature reduction and that unstable Fe species are dissolved into acid solution. The difference in Fe concentration from the core region to the surface and strong O-Fe bonding may drive the outward diffusion of Fe to the highly corrugated Pt-skeleton, and the resulting highly dispersed surface FeOx is stable in acidic medium, leading to the construction of a PtBFe@Pt-FeOx architecture. The as prepared PtFe/C catalyst demonstrates a higher activity and comparable durability for the oxygen reduction reaction compared with a Pt/C catalyst, which might be due to the synergetic effect of surface and subsurface Fe species in the PtFe/C catalyst.
基金
This work was financially supported by the Ministry of Science and Technology of China (Grants 2012CB215500 and 2013CB933100) and the National Natural Science Foundation of China (Grants 21103178 and 21033009).