Iron Phosphide Nanostructures Produced from a Single-Source Organometallic Precursor:  Nanorods, Bundles, Crosses, and Spherulites

Abstract

Single-source molecular precursors were found to produce iron phosphide materials. In a surfactant system of trioctylamine and oleic acid, H2Fe3(CO)9PtBu reacted to form Fe4(CO)12(PtBu)2, which decomposed to give Fe2P nanorods and "bundles." Control of the morphology obtained was possible by varying the surfactant system; addition of increasing amounts of oleic acid resulted in crystal splitting, while the addition of microliter amounts of an alkane enhanced the crystal splitting to give sheaflike structures. The different morphologies seen were attributed to imperfect crystal growth mechanisms.

Magnetic Fe2P nanowires and Fe2P@C core@shell nanocables

“…5(b)) also demonstrate that the Fe 2 P nanowire core grows along the [001] direction of the hexagonal Fe 2 P structure. The preferred growth direction of the resulting 1-D Fe 2 P nanostructures is consistent with the previously reported cases [22,23,28,37,38]. Meanwhile, In our experiments, two kinds of Fe precursors, commercial elemental iron powder and a molecular iron precursor (ferrocene, Fe(C 5 H 5 ) 2 ), were separately used to prepare Fe 2 P nanostructures.…”

“…In general, Refs. [14,15,[21][22][23][24][25][26][27][28]38] suggest that the formation of a homogeneous solution of reactants favors the growth of size-uniform nanocrystals. When the vacuum-sealed ampoule is quickly transferred into a 400 °C furnace from the 220 °C furnace, the reaction between Fe(C 5 H 5 ) 2 and PPh 3 progresses very rapidly, and a black product of Fe 2 P@C nanocables results (Fig.…”

“…Meanwhile, the O'Brien group reported an one-pot reflux route for the synthesis of CoP nanowires through thermal decomposition of [Co(acac) 2 ] (acac = acetylacetonate) and tetradecylphosphonic acid in a mixed surfactant solution of trioctylphosphine oxide (TOPO) and hexadecylamine (HDA) at 340 °C for 3 h [27], in which the anisotropic 1-D growth of CoP nanowires was achieved by employing selective adsorption of surfactants to control the growth rates of different facets. Recently, Whitmire and co-workers showed that Fe 2 P nanorods and bundles can be prepared by the thermal decomposition of a single-source precursor (H 2 Fe 3 (CO) 9 P t Bu) in a mixture of trioctylamine (TOA) and oleic acid (OAc) at temperatures from 315 to 330 °C depending on the ratios of TOA and OA [28]. In these methods, a mixture of two or more surfactants was required, and the formation of 1-D transition metal phosphide nanostructures is usually explained by the cooperative effects of the surfactants, such as selective adsorption, along with the intrinsically anisotropic crystal structure of the phosphides [22][23][24][25][26][27][28].…”

“…Recently, Whitmire and co-workers showed that Fe 2 P nanorods and bundles can be prepared by the thermal decomposition of a single-source precursor (H 2 Fe 3 (CO) 9 P t Bu) in a mixture of trioctylamine (TOA) and oleic acid (OAc) at temperatures from 315 to 330 °C depending on the ratios of TOA and OA [28]. In these methods, a mixture of two or more surfactants was required, and the formation of 1-D transition metal phosphide nanostructures is usually explained by the cooperative effects of the surfactants, such as selective adsorption, along with the intrinsically anisotropic crystal structure of the phosphides [22][23][24][25][26][27][28]. Other methods, such as high-temperature thermal treatment of single-molecule precursors [29], hydrothermal and solvothermal methods [30,31], the de-silylation strategy [21,32], phosphate reduction [33], and metal particle conversion in solution [34][35][36], produced spherical nanoparticles of transition metal phosphides.…”

The structural evolution and diffusion during the chemical transformation from cobalt to cobalt phosphide nanoparticles

“…[26][27][28][29] Cobalt phosphides have recently received increased attention due to their catalytic and magnetic properties as well as their potential as a promising anode material. [30][31][32][33][34] Recently, we have reported a controlled synthesis of hyperbranched Co 2 P using tri-n-octylphosphine oxide (TOPO) as a phosphorus source.…”