Fe-Pt nanoparticles

In 2000, Sun and co-workers succeeded in synthesis of monodispersed Fe/Pt nanoparticles by the reduction of platinum acetylacetonate and decomposition of Fe(CO)5 in the presence of oleic acid and oleylamine stabilizers [18]. The Fe/Pt nanoparticle composition is readily controlled, and the size is tunable from 3 to 10 nm in diameter with a standard deviation of less than 5%. For practical use, we developed the novel symthetic method of FePt nanoparticles by the polyol reduction of platinum acetylacetonate (Pt(acac)2) and iron acetylacetonate (Fe(acac)3) in the presence of oleic acid and oleylamine stabilizers in di- -octylether [19,20]. The Fe contents in FePt nanoparticles can be tuned from 23 to 67atomic%, and the particle sizes are not significantly affected by the compositions, retaining to be 3.1 nm with a very narrow size distribution, as shown in Figure 6. 

Trimetallic particles may also be obtained by this route. Thus Nikles reported the preparation of Fe-Co-Pt nanoparticles using a procedure similar to those used for the synthesis of Fe-Pt nanoparticles but upon mixing an additional cobalt precursor. Several compositions were obtained, and the particles were shown to self-assemble upon removal of the solvent (Figure 4). In a similar way, Fe-Pt-Cu particles could be obtained starting upon adding... 

They have the face-centered tetragonal structure and thus obtain a unique property of recording advantage of large coercivity when in room temperature, no matter how small the particles are. Prepared by joint thermolysis in the presence of oleic acid and oleylamine, FE—Pt nanoparticles have a narrow size distribution. After further heating, a protective film is formed on the surface of alloys, which remain about the same size. 

Gibot P, Tronc E, Chaneac C, Johvet JP, Fiorani D, Testa AM. (Co, Fe) Pt nanoparticles by aqueous route self-assembling, thermal and magnetic properties. J Magn Magn Mater 2005 290 555-8. 

Kim J, Lee Y, Sun SH (2010) Structurally ordered Fe-Pt nanoparticles and their enhanced catalysis for oxygen reduction reaction. J Am Chem Soc 132 4996... 

Formation of single-walled carbon nanotubes (SWNTs) was found to be catalyzed by metal nanoparticles [207]. Wang et al. [114] investigated bimetallic catalysts such as FeRu and FePt in the size range of 0.5-3 nm for the efficient growth of SWNTs on flat surfaces. When compared with single-component catalysts such as Fe, Ru, and Pt of similar size, bimetallic catalysts Fe/Ru and Fe/Pt produced at least 200% more SWNTs [114]. 

An aluminum electrode modified by a chemically deposited palladium pen-tacyanonitrosylferrate film was reported in [33]. Vitreous carbon electrode modified with cobalt phthalocyanine was used in [34]. Electrocatalytic activity of nanos-tructured polymeric tetraruthenated porphyrin film was studied in [35]. Codeposition of Pt nanoparticles and Fe(III) species on glassy-carbon electrode resulted in significant catalytic activity in nitrite oxidation [36]. It was shown that the pho-tocatalytic oxidation at a Ti02/Ti film electrode can be electrochemically promoted [37]. 

Kotobuki, M., Watanabe, A., Uchida, H., Yamashita, H., and Watanabe, M. High catalytic performance of Pt-Fe alloy nanoparticles supported in mordenite pores for preferential CO oxidation in H2-rich gas. Applied Catalysis. A, General, 2006, 307, 275. 

Fig. 3 shows a FE-SEM image of the Pt/C sample. White dots correspond to Pt particles. The particle sizes are about 3-8 nm and the Pt nanoparticles were... 

S. Wang and X. Lin. Electrodeposition of Pt-Fe(lll) nanoparticle on glassy carbon electrode for electrochemical nitric oxide sensor, Eiectrochim. Acta 50, 2887-2891 (2005). 

Subsequently, Pt-Fe(III) nanoparticles, carbon nanotube-gold nanoparticles, and copper nanoparticles were also used to design NO electrochemical sensors (Wang et al. 2004a Wang and Lin 2005 Zhang and Oyama 2005 Polsky et al. 2006). 

As can be known, the second additive can change the electric performance of a noble metal, so that the catalytic ability of the alloy catalyst will be improved a lot. In this section, we investigate the relation between the structural properties and the PROX catalytic performance of PtFe alloy nanoparticles catalysts supported with alumina. Table 29.1 shows the compositions of the samples used in this study. The weight percent of Pt was fixed as 3 wt% in the samples three Fe/Pt atomic ratios (I/I, 2/1, and 3/1) of PtFe alloy nanoparticle catalysts were prepared. 

This is the case of easily oxidizable metals (such as Ni, Fe, and Ru), since H desorption is superposed with the OH adsorption PtM alloys (M = Co [19], Ni [20], etc.), due to the electronic influence of transition metals leading to strong attenuation of the charge of Hupo and small Pt nanoparticles [1] where the Hupd charge strongly decreases below 3 nm size. 

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