Formation and emission spectroscopy of laser-generated nanoparticles
2002 (English)In: Smart Materials and Structures, Vol. 11, 631-639 p.Article in journal (Refereed) Published
Fe nanoparticles, with both fcc and bcc structures and with a C shell that protects against oxidation, were generated by the laser-assisted photolytic chemical vapor decomposition of ferrocene (FeCp2). Amorphous W and WN0,3 nanoparticles were formed by laser ablation (LA) of solid W in Ar and in N2 ambient, respectively. Laser-assisted chemical vapor deposition of W yielded crystalline W nanoparticles (β phase) from a WF6/H2/Ar gas mixture. ArF excimer laser was used as the radiation source in all the experiments. Measurements and analysis of the emitted blackbody-like radiation from the laser heated particles were performed and dominant cooling processes such as evaporation and heat transfer by the ambient gases were identified. The particles could be heated up to the boiling and melting point of Fe and W, respectively. Lognormal particle size distributions were found for Fe/C and W nanoparticles generated by vapor decomposition or deposition processes respectively, and then modeled at low particle concentration (with no coagulation). The thickness of the C shell was practically independent of the laser fluence, while the size of the Fe core could be varied for the Fe/C particles. The LA yielded no lognormal-type distribution for the amorphous WN0,3 particles.
Place, publisher, year, edition, pages
2002. Vol. 11, 631-639 p.
IdentifiersURN: urn:nbn:se:uu:diva-69713DOI: doi:10.1088/0964-1726/11/5/302OAI: oai:DiVA.org:uu-69713DiVA: diva2:97624