Continuous production of iron-based nanocrystals by laser pyrolysis. Effect of operating variables on size, composition and magnetic response

Abstract

Well dispersed iron-based magnetic nanoparticles have been prepared by gas phase laser-driven decomposition of iron pentacarbonyl. Agglomeration of the newly synthesized nanoparticles could be avoided by using a liquid collection system in which the exit stream from the laser reactor was bubbled through triethylene glycol (TREG). The effect of different experimental parameters (precursor concentration, laser power, working pressure, residence time) was studied and, by selecting the appropriate conditions, the size of the resulting magnetic nanocrystals could be tuned from ultrasmall (ca. 2.5 nm) to around 12 nm. For nanoparticle sizes around 10 nm and larger a metallic iron core could be preserved. These iron/iron oxide core-shell compositions exhibit very high values of magnetization, 127 emu g(-1).

Iron Oxide Nanoparticles for Biomedical Applications: A Perspective on Synthesis, Drugs, Antimicrobial Activity, and Toxicity

“…It is less expensive than other methods, since it operates at atmospheric pressure [ 35 , 62 ]. Factors such as precursors concentration, working pressure and laser intensity directly interfere with size and magnetization of the resulting nanoparticles [ 63 ].…”

Facile production of stable silicon nanoparticles: laser chemistry coupled to in situ stabilization via room temperature hydrosilylation

“…1c) demonstrate the Fd3m crystalline structure of the as-prepared silicon nanocrystals. 13,32,40 Raman spectroscopy of the as-prepared Si nanocrystals is presented in Fig. 1e shift to lower wave-number values accompanied by an asymmetrical broadening of the Raman spectrum can be attributed to the presence of additional phonon modes that become active beyond the Brillouin zone with decreasing nanocrystal sizes.…”

Laser-Assisted Production of Carbon-Encapsulated Pt-Co Alloy Nanoparticles for Preferential Oxidation of Carbon Monoxide

“…The synthesis of Pt x Co y /C composite nanoparticles with different compositions has been carried out by laser pyrolysis in a continuous flow reactor described elsewhere (Martínez et al, 2012 ; Malumbres et al, 2013 , 2015 ). The starting solution employed for the synthesis of Pt x Co y /C was prepared by dissolving Pt(acac) 2 (47 mg, 0.12 mmol) and the corresponding amount of Co(acac) 3 [11 mg (0.04 mmol) or 30 mg (0.12 mmol)] in toluene, to get a molar ratio Pt:Co = 3 or Pt:Co = 1.…”