Fast High-Resolution Multi-Elemental Mapping of Phosphate Pellets Using Laser Induced Breakdown Spectroscopy

Abstract

Recent years have seen a growing trend towards analytical techniques capable of conducting spatially resolved analyses of surfaces for industrial, nanotechnology, geological and biomedical applications. Depending on the application, spatially resolved measurements are required to provide a better understanding of the sample surface composition with significant advantages over conventional bulk analyses. The recent developments of the LIBS technique and its simplicity of use have allowed the development of systems capable of performing multi-element imaging analyses of major and trace elements with ~50 μm (or lower) spatial resolution at fast acquisition speeds up to kHz per pixel. LIBS technology enables systematic and selective ways based on the physics of atomic emission spectroscopy (AES). Complex structures are revealed by LIBS imaging at ultrafast speed. This paper presents results on laser-induced breakdown spectroscopy (LIBS) performing fast high-resolution multi-elemental mappings of Phosphate samples. Phosphate Pellets samples were laser scanned at a repetition rate of 1 kHz with a spatial resolution of 50 μm, using the Mission: Coriosity platform from ELEMISSION Inc. The elemental mappings of the 10 mm2 surfaces for 6 elements were obtained, revealing high levels of detail and complexity in the elements distributions. Advanced graphical algorithms allow direct visualization of the distribution of several elements on the same image. In particular, LIBS imaging has been used for multi-elements surface mapping of Phosphate Pellets, and show specific clustering composition, indicating that line intensity of a given analyte element is not only related to that analyte, but also to other elements present in the samples. This last statement has been verified using multivariate approach for calibration and prediction of elemental concentration in Phosphate Pellets.