On-line monitoring of composite nanoparticles synthesized in a pre-industrial laser pyrolysis reactor using Laser-Induced Breakdown Spectroscopy

Abstract

Laser-Induced Breakdown Spectroscopy (LIBS) was employed for on-line and real time process monitoring during nanoparticle production by laser pyrolysis. Laser pyrolysis has proved to be a reliable and versatile method for nanoparticle production. However, an on-line and real time monitoring system could greatly enhance the process optimization and accordingly improve its performances. For this purpose, experiments aiming at demonstrating the feasibility of an on-line monitoring system for silicon carbide nanoparticle production using the LIBS technique were carried out. Nanosecond laser pulses were focused into a cell through which part of the nanoparticle flux diverted from the production process was flowed for LIBS analysis purposes. The nanoparticles were vaporized within the laser-induced plasma created in argon used as background gas in the process. Temporally-resolved emission spectroscopy measurements were performed in order to monitor nanoparticle stoichiometry. Promising results were obtained and on-line Si/C X stoichiometry was successfully observed. These results put forward the possibility of real time correction of the nanoparticle stoichiometry during the production process.

A critical review of recent progress in analytical laser-induced breakdown spectroscopy

“…The investigation of LIBS specifically for the online monitoring of nanoparticle (NP) streams in gas phase was reported by Amodeo et al [179], successfully achieving quantitative analysis of silicon carbide NPs in the size range of 20 to 100 nm. Noll et al reported size-resolved (20 to 800 nm) measurements of ultrafine particulate matter using LIBS for the analysis of calcium chloride particles [180].…”

Mechanical properties of nanostructured silicon carbide consolidated by spark plasma sintering

“…23 The experimental parameters were chosen in order to obtain a very fine and uniform particles morphology while reactive gas flows were adjusted to produce stoichiometric powder at a high production rate of about 1 kg/h. In some cases, the sintering additive boron element was introduced during the laser synthesis by adding BCl 3 to the reactant gases to produce composite Si/C/B nano-powders.…”

On-line determination of nanometric and sub-micrometric particle physicochemical characteristics using spectral imaging-aided Laser-Induced Breakdown Spectroscopy coupled with a Scanning Mobility Particle Sizer

“…LIBS has already been utilized for on-line monitoring of metal laden aerosols in industrial production, combustion processes [12,13,14], environmental purposes [15,16] and promising results were obtained. More recently, it has been applied to on-line and real time process monitoring during nanoparticle production [17]. LIBS was consequently selected for monitoring purposes near the production processes.…”