A nanoporous PtFe (np-PtFe) alloy composed of a single face-centered-cubic FePt phase has been fabricated by electrochemically dealloying an amorphousFe 60 Pt 10 B 30 alloy in 0.1 mol L −1 H 2 SO 4 solution. The np-PtFe alloy possesses a fine bicontinuous ligament/channel structure with average ligament and pore sizes of about 7 and 5 nm, respectively. The np-PtFe alloy exhibits superior electrocatalytic
摘要 通过在 0.1 mol L -1 H 2 SO 4 溶液中对非晶 Fe 60 Pt 10 B 30 合金进行电化学脱合金,制备了一种由单一面心立方 FePt 相组成的纳米多孔 PtFe (np-PtFe) 合金。np-PtFe 合金具有精细的双连续韧带/通道结构,平均韧带和孔径分别约为 7 和 5 nm。与商用庄信万丰 Pt/C 催化剂相比,np-PtFe 合金对酸性介质中的甲醇氧化反应表现出优异的电催化活性和饱和磁化强度为 19.09 emu/g 的软磁特性。
Interfacial disorder in the L10 FePt particles capped with amorphous Al2O3
作者:Y. K. Takahashi、K. Hono
DOI:10.1063/1.1641175
日期:2004.1.19
L10-FePt particlesdisorder at the interface when an amorphousAl2O3 layer is capped on an ordered FePt particulate film at room temperature. The coercivity decreases drastically as a result. Interfacialdisordering does not progress when the capped layer is deposited at elevated temperature, indicating that the disordering is driven by the strain at the interface. The FePt particulate film becomes
We have studied L10-FePt thinfilms with a Bi underlayer. Experimental results show that the ordering temperature of the L10-FePt film can be lowered down to 300–350°C and the in-plane coercivity HC of the film is obviously enhanced by introduction of a Bi underlayer. After annealing at 400°C for 20min, a Bi∕FePt film realizes a HC of 13.5kOe and the ratio of the remnant magnetization Mr to the saturation
我们研究了具有 Bi 底层的 L10-FePt 薄膜。实验结果表明,通过引入 Bi 底层,L10-FePt 薄膜的有序化温度可以降低到 300-350°C,薄膜的面内矫顽力 HC 明显提高。在 400°C 下退火 20 分钟后,Bi ∕ FePt 薄膜实现了 13.5kOe 的 HC 和高达 0.93 的剩余磁化强度 Mr 与饱和度 MS 的比值。通过考虑与 Bi 扩散相关的 Fe 和 Pt 的大扩散率,可以理解 L10-FePt 薄膜的有序温度的降低和磁性能的增强。
Studies of Transition Metal Dissolution from Combinatorially Sputtered, Nanostructured Pt[sub 1−x]M[sub x] (M = Fe, Ni; 0<x<1) Electrocatalysts for PEM Fuel Cells
作者:A. Bonakdarpour、J. Wenzel、D. A. Stevens、S. Sheng、T. L. Monchesky、R. Löbel、R. T. Atanasoski、A. K. Schmoeckel、G. D. Vernstrom、M. K. Debe、J. R. Dahn
DOI:10.1149/1.1828971
日期:——
The dissolution of Fe and NifromPt 1 - xMx (M = Fe, Ni; 0 0.6, the lattice constant expands indicating that transitionmetals dissolve also from the bulk. X-ray photoelectron spectroscopy results show complete removal of surface Ni (Fe) after acid treatment at 80°C for all compositions. The results of the acid treatments compare well to the composition changes that occur when a Pt 1 - xFex or
Fe 和 Ni 从 Pt 溶解 1 - x M x (M = Fe, Ni; 0 0.6, 晶格常数扩大表明过渡金属也从体中溶解。X 射线光电子能谱结果显示表面 Ni ( Fe) 在 80°C 下对所有组合物进行酸处理后。酸处理的结果与在操作中使用 Pt 1 - x Fe x 或 Pt 1 - x Ni x 组合催化剂库时发生的成分变化相当PEM 燃料电池。
Thermally stable exchange-biased magnetic tunnel junctions over 400 °C
Exchange-biasedmagnetictunneljunctions (MTJs) with interposed Fe1−xPtx metal alloy layers between the Al oxide barrier and the ferromagnetic electrodes maintain large tunneling magnetoresistance (TMR) after thermal treatment in excess of 400 °C, owing to an improved barrier interface. After 400 °C annealing, TMRs of MTJs with Fe1−xPtx (x=0.1–0.2) exhibit over 40% and retain 30% TMR after 420 °C