Role of different platinum precursors on the formation and reaction mechanism of FePt nanoparticles and their electrocatalytic performance towards methanol oxidation

Abstract

We report the formation mechanism of FePt nanoparticles (NPs) by a high temperature polyol method using an equimolar ratio of Fe and Pt-precursor with different Pt-precursors. Pt(acac)2, PtCl2, PtCl4 and H2PtCl6·H2O were used as Pt-precursors and Fe(acac)3 as the only Fe-precursor. Different stoichiometric compositions along with variation in size were obtained by using different precursors of Pt. Nearly, equiatomic FePt having a size ~2 nm was formed with Pt(acac)2. However, Pt rich phases were formed using all other precursors with a size ranging between 3.6 to 6.4 nm. It was found that the atomic percentage (at%) of Fe in the FePt NPs depends on the reaction parameters. The decomposition behaviour of Fe and Pt-precursors were examined by vibrating sample magnetometer and thermogravimetric measurements. A possible reaction mechanism for Fe depleted FePt formation is proposed which suggests that the reduction potential and decomposition behaviour of the organic and inorganic salts of Pt significantly modify the nucleation behaviour. The electrocatalytic properties of all the four nanomaterials towards methanol oxidation have been investigated by cyclic voltammetry. It is found that Fe19Pt81 with an average size of 6.2 nm shows the highest catalytic response.

Interfacial surfactant competition and its impact on poly(ethylene oxide)/Au and poly(ethylene oxide)/Ag nanocomposite properties

“…TGA results of oleylamine,35 oleic acid,36 oleylamine/oleic acid mixture37,38 (1:1 by volume), and Au and Ag nanoparticles that were surface modified with oleylamine/oleic acid mixture are presented in Figure 2. Both pure oleylamine and oleic acid TGA profiles showed single degradation events at ~240 and 280°C, respectively.…”

“…TGA plots of oleylamine,35 oleic acid,36 oleylamine/oleic acid mixture,37,38 and oleylamine/oleic acid-modified Au and Ag nanoparticles.…”

Recent Advances in FePt Nanoparticles for Biomedicine

“…Based on this method, Chou et al [21] prepared FePt nanoparticles with 3, 6, and 12 nm diameters by heating a reaction mixture of Pt(acac) 2 , Fe(CO) 5 , 1,2-hexadecanediol, dioctyl ether, oleylamine, and oleic acid to 297 ∘ C and then using ethanol to extract the resultant material. Sahu et al [33]…”

Nickel platinum (NixPt1−x) nanoalloy monodisperse particles without the core–shell structure by colloidal synthesis

“…Ni(acac) 2 thermally decomposes at z230 C (ref. 39) while Pt(acac) 2 at z160 C. 47 As a consequence, in the same medium at temperatures around 220-230 C, the Pt precursor is decomposed and reduced faster and before Ni, resulting in the formation of a Pt nucleus. Then, once Ni reduction occurs, Ni atoms settle on the Pt nuclei surface, forming a shell.…”