Time resolved VUV LIBS – Limit of Detection (LOD) Optimization for Light Elements in Metals
Laser Induced Breakdown Spectroscopy (LIBS) is an analytical technique used to classify and potentially quantify elements in complex hosts (or matrices). It is particularly useful for light elements for which techniques like X-ray fluorescence are not so effective. LIBS is normally confined to the UV-Visible-NIR region of the electromagnetic spectrum (300 – 1000 nm).
However, many light elements have their strongest emission lines in the VUV as they originate from transition from excited to lower (usually ground) states in multiply charged ions rather than atoms. To this end DCU has established a VUV LIBS laboratory to exploit the anticipated signal-to-background (SBR) and concomitant limit-of-detection (LOD) gains expected in the VUV.
Most recently DCU have demonstrated Double-Pulse LIBS where a pre plasma formed by one laser is pumped after an optimal delay to enhance the SBR and LOD for carbon and sulphur detection in steel . This project is concerned with adding time resolution to the VUV LIBS. This we will do by replacing a time integrating VUV CCD with a time resolving VUV photomultiplier. A VM520 Normal Incidence VUV spectrometer will be converted back to monochromator mode so that the spectral line of interest for LIBS can be wavelength selected and detected by a fast response (nanosecond) photomultiplier tube, sensitive in the VUV.
Miss Syedah Sadaf Zehra has graduated from Sir Syed University of Engineering and Technology in Biomedical Engineering, in 2005. She earned her M.Sc. degree in Biomedical Engineering from the same University in 2012. She joined Sir Syed University as a research Assistant in 2007 then she continued there as a faculty member till 2015.
During this tenure, she was involved in various academic activities in B.S. and M.Sc. Biomedical Engineering programs. Miss Zehra joined EXTATIC Erasmus Mundus Joint Doctorate program in April 2015. Her project title is “Time resolved VUV LIBS – Limit of Detection (LOD) Optimization for Light Elements in Metals”. She is particularly interested in working on VUV Time resolved LIBS and its applications.