cm034443o_si_001.pdf (33.89 kB)
Application of De-silylation Strategies to the Preparation of Transition Metal Pnictide Nanocrystals: The Case of FeP
journal contribution
posted on 2003-09-24, 00:00 authored by Susanthri C. Perera, Petru S. Fodor, Georgy M. Tsoi, Lowell E. Wenger, Stephanie L. BrockPhase-pure FeP nanoparticles have been synthesized by the reaction of iron(III) acetylacetonate with tris(trimethylsilyl)phosphine at temperatures of 240−320 °C using trioctylphosphine oxide as a solvent and dodecylamine (DA), myristic acid (MA), or hexylphosphonic
acid (HPA) as additional capping groups (ligands). The DA-capped particles prepared at
260 °C have an average diameter of 4.65 ± 0.74 nm with FeP being the only observed
crystalline phase. Elemental analyses indicate a high percentage yield of FeP (85%) and
are consistent with 12% TOPO incorporation in the product. The addition of MA has results
similar to those of the addition of DA, whereas addition of HPA seems to inhibit crystallite
growth, resulting in very small (ca. 1 nm) or amorphous particles that are difficult to isolate.
Magnetic susceptibility data on DA-capped FeP suggest that the moments within each
particle are coupled antiferromagnetically, at least over a short range; however, there is no
evidence of a Néel transition, in contrast to bulk FeP. It is likely that the FeP particles
produced by this route are too small (ca. 5 nm) relative to the magnetic cell (2.9 nm) for the
onset of long-range helical antiferromagnetic order, even at low temperatures (5 K) and
fields (0.010 T).