Purchase of a Tandem LA-LIBS femtosecond laser for the UK

This grant has funded the installation of an integrated femtosecond laser ablation (fs-LA) and laser induced breakdown spectroscopy (LIBS) system. This will provide a step change in environmental research capability via concurrent analysis of major and trace elements spanning the entire periodic table, a wide-range of isotope ratios and nanoscale depth profiles for a vast range of materials. The new facility will be unique to the environmental community in the UK and Europe, and will be used to:
1. Identify the sources and fates of marine, freshwater and atmospheric particulate pollution (microplastic, dust and other) and how they influence metal cycling and vectoring through processes such as surface adsorption, leaching and biofilm formation
2. Monitor the growth of marine organisms and their response to environmental stresses, including oyster bed restoration in UK waters
3. Perform novel micro- to nano-scale chemical and isotopic measurements of accessory minerals such as zircon and apatite to transform our understanding of early Earth processes and the development of plate tectonics
4. Give unprecedented insight into the formation of carbonates in hydrothermal and brittle-fault settings to better understand links between fault movement, (neo)tectonics and ore mineralisation
5. Provide new constraints on magmatic-hydrothermal and weathering processes leading to critical metal and other ore-formation; via concurrent analysis of non-metals (e.g. H, S, C, O and halogens) in fluid inclusions and economic minerals by LIBS and metals and isotopes by (MC)-ICP-MS
6. Enable in-situ geochemical characterization and nanoscale depth profiling for a wide-range of materials (e.g. polymers, biofilms, tissue, biominerals), by overcoming the currently limiting requirement for matrix-matched reference materials
The facility is housed at the University of Portsmouth, will not form part of a NERC service and facility, but will be open for use by the UK scientific community.

Earth and environmental scientists tackle diverse issues ranging from the formation of Earth to the fate of ecosystems being stressed by pollution. This requires us to measure the chemical composition of many different samples, including minerals, plastics, dust, and biological materials; data that allows us to link physical and biological process (e.g. growth of minerals, breakdown of plastic in the environment, corrosion, dispersal of dust) with chemical ones (e.g. uptake of metals in minerals, release of toxic elements from plastics, transfer of polluting chemicals to plants and animals). Only then can we fully determine sustainable solutions to complex environmental problems, such as (1) how to locate and sustainably mine metals that are critical for building low-carbon infrastructure, (2) how dangerous microplastics are in rivers and oceans, and (3) how to reduce harmful air pollution. Measurement of such a broad range of materials usually requires a multitude of different instruments and methods. In addition, for many materials (e.g. plastic, dust) it is difficult to measure very small fragments in a controlled way. We propose the use of a new instrument, the first of its kind in the UK, that will allow analysis of a vast range of Earth materials and difficult to measure elements to provide high quality data critical for addressing geo-environmental problems.
The new instrument capitalises on recent innovations in laser technology, bringing together ultrafast femtosecond laser ablation (fs-LA) with laser induced breakdown spectroscopy (LIBS) into a single system (fs-LA-LIBS). It is uniquely capable of analysing a wide range of materials, as the very short duration pulse laser (femtosecond (fs) or one quadrillionth of a second!) ejects only a very thin surface layer of material and does not heat the sample below. This allows sensitive materials, such as plastic, liquids, biological samples and dust, to be rapidly analysed for their chemical composition. This is measured simultaneously in two ways: 1) LIBS - the laser energy ejects and excites atoms, which emit optical radiation (light) as they cool. Spectrometers measure the wavelength of this optical radiation and convert it into a chemical analysis of the sample, including for elements such as non-metals that are very difficult to measure in other ways. 2) LA-, the tiny volume of ejected sample is swept away by a stream of gas into a mass spectrometer, where it enters a 7000oC plasma, (as hot as the Sun’s surface), breaking down any remaining molecules and producing charged ions. These are separated by the mass spectrometer according to their mass and charge, providing highly-sensitive measurement of the concentration of trace elements and ratios of different isotopes in the sample.
The combination of these technologies in one instrument capable of rapid analysis will be unique to the UK and Europe, and will provide the data required to tackle many major environmental challenges.