An optimal configuration for spark-induced breakdown spectroscopy for bulk minerals aimed at planetary analysis
Spark-induced breakdown spectroscopy (SIBS) utilizes an electric spark for inducing a strong plasma for collecting atomic emissions. The spark is an electric discharge characterized by a high voltage and low current, which occurs when the applied voltage between electrodes is higher than the breakdown voltage of the ambient surrounding the electrodes. This study analyses the potential for complementing a compact SIBS over conventional laser-induced breakdown spectroscopy (LIBS) in discriminating rocks and soils for planetary missions. Targeting bulky solids using the SIBS has not been successful in the past, and therefore a series of optimizations of electrode positioning and electrode materials was performed in this work. The limit of detection (LOD) was enhanced up to 4 times from when LIBS was used, showing a change from 78 ppm to 20 ppm from LIBS to SIBS. Within the same CCD gate delay time and width, the signal intensity by SIBS was substantially higher than LIBS in three orders of magnitude due to the bigger energy of plasma generated. Changing the electrode material and locating the optimum position of the electrodes were considered for optimizing the current SIBS set up for potential planetary missions.