Laser-induced breakdown spectroscopy (LIBS) is an atomic-emission spectroscopy technique that enables rapid chemical analysis of a wide range of materials ranging from metals, semiconductors, glasses, biological tissues, plastics, soils, thin-paint coating, and electronic materials.
LIBS relies on focusing short and high energy laser pulses onto the surface of a target sample to generate a plasma of small amounts of ablated material. The extremely high temperatures within the early plasma (>100,000K) cause the ablated material to dissociate into excited atomic and ionic species and during the cooling process the characteristic atomic emission lines can be detected by a spectrograph. The method enables fast and sensitive chemical analysis of in principle any kind of matter (solid-liquid or gas) without the need for sample preparation and with detection limits typically in the low-PPMs for heavy metal elements.
LIBS has received substantially increased interest over recent years as a result of the development of more compact, even hand-held, systems that enables in-field use and construction of tools for on-line material analysis. This development has been made possible by the increased availability of more compact system components such as e.g.the laser sources used. Particularly interesting is LIBS’s potential use in tools for on-line monitoring of industrial processes, e.g for the metal industry. An example of an application that would strongly benefit from more compact and industrial-grade LIBS systems is Aluminium recycling. Aluminium is in principle 100% recyclable and the use of recycled aluminium requires only 5% of the energy used in extraction of virgin minerals to produce aluminium. The potential of a direct classification and sorting of recycled aluminium flows is therefore huge, both in terms of economical benefits for the aluminium producers and minimised environmental impacts.