Laser Induced Plasma Spectroscopy for the Characterization of Aerosols and Particulates

Abstract

Laser induced plasma spectroscopy is beginning to find useful applications in the real time in situ detection of particulates and aerosols suspended in gases. Although the technique is almost 40 years old, it has become increasingly practical for this application during the last decade due to the development of more reliable lasers and optical detection systems, an improved understanding of the physical processes involved, and new data collection and analysis strategies. There is a pressing need for such detection techniques for industrial process and atmospheric monitoring. In this review, we examine literature concerned with the process of optical breakdown by focused lasers in gases, the role of particles in this process, and the characterization of particles using laser induced plasmas.

Aerosol analysis by micro laser-induced breakdown spectroscopy: A new protocol for particulate matter characterization in filters

“…One of the main LIBS advantages include the high working speed compared to other techniques. LIBS applications to aerosol analysis have been reported previously [26,[31][32][33], however, to the best of our knowledge, we were the first to demonstrate LIBS scanning microanalysis potential use for characterizing ambient air aerosol particles deposited on filters.…”

Comparing several atomic spectrometric methods to the super stars: special emphasis on laser induced breakdown spectrometry, LIBS, a future super star

“…For particle analysis, the parameters of interest include size distributions, number densities, and species composition. Based on recent publications, [132][133][134][135] LIBS proved to be a suitable technique for the detection of particles and aerosols, with resulting spectra subsequently analyzed for both species composition and total particle mass and size.…”

Shadowgraph of Pulse CO₂ Laser Induced Breakdown in Different Pressure Air

“…A focused Q-switched ruby laser of tens-of megawatts produced a spark in air was first reported in 1963 by Maker et al, which was similar to that of electric breakdown between electrodes [1]. Laser induced gas breakdown has many practical applications such as laser propulsion [2], detection of environmental pollutants [3], ignition systems [4], as well as production of soft and hard-X ray radiation [5]. Typically, a 200 mJ/pulse from a laser with 70 ns pulse width, corresponding to a focused power density of 10 GW/cm 2 is sufficient for plasma generation.…”