Laser-Induced Breakdown Spectroscopy (Libs): An Innovative Tool for Elemental Analysis of Soils

Laser-induced breakdown spectroscopy (LIBS) is an elemental analysis technique that is based on the measurement of atomic emissions generated on a sample surface by a laser-induced microplasma. Analytical applications of LIBS, namely optical emission spectroscopy of laser- induced plasmas, have been constantly growing thanks to its intrinsic conceptual simplicity and versatility. Qualitative and quantitative analysis can be performed by LIBS both by drawing calibration lines and by using calibration-free methods and some of its features, so as fast multi- elemental response, micro-destructiveness, instrumentation portability, have rendered it particularly suitable for analytical applications in the field of environmental science, space exploration and cultural heritage. LIBS can be a useful tool for direct spectro-chemical analysis of trace elements in complex matrices like minerals and soil. This paper aimed to analyzing some element concentration in soil. Reports and discusses LIBS achievements in these areas and results obtained for soils samples. Laser-induced breakdown spectroscopy (LIBS) is also called laser-induced plasma spectrometry (LIPS) or laser spark spectrometry (LSS). It is a total multi-elemental analytical technique based on atomic emission spectroscopy (AES). Compared to the conventional elemental analytical methods, LIBS has numerous potential advantages such as simple and compact experimental setup, less sample preparation, less destructive surface analysis, remote in-situ analysis in hostile environments for hazardous or inaccessible targets, etc. (1). LIBS utilizes a high-energy laser pulse as the vaporization, atomization, and excitation source to create a high-temperature microplasma at the surface of the target. The elements contained in the sample are vaporized and excited in the hot plasma to generate an atomic and ionic spectrum which is characteristic of the elemental composition of the target. Each element has its unique emission lines working as the fingerprint of the element. After being spectrally resolved, the wavelength of the emission line is used to identify the existence of the elements, and the background-subtracted peak intensity at the chosen emission line is used to quantify the elemental composition of the target (2). The analysis of the LIBS spectral data collected from soil samples is of great significance in evaluating the quantitative analytical ability of LIBS in soil metals analysis. Our goals were to analyzing the LIBS spectral information and to quantitatively determine some element concentrations in soils.