Comparison of three nanoparticle deposition techniques potentially applicable to elemental mapping by nanoparticle-enhanced laser-induced breakdown spectroscopy

In this study, we compared the applicability of three nanoparticle deposition techniques (spray coating, spark discharge nanoparticle generation, magnetron sputtering) towards elemental mapping by nanoparticle-enhanced laser -induced breakdown spectroscopy (NE-LIBS). It was found that sputtering followed by a thermal treatment at 550 degrees C can provide a homogenous, practical and controllable way of NE-LIBS sample preparation with gold nanoparticles. The laser ablation properties of the created NP layer was also studied in detail and it was established that a 200 mu m laser spot size is good compromise between the NE-LIBS signal enhancement and the spatial resolution required for mapping. A signal enhancement of about a factor of 10 with good repeatability (ca. 5 %RSD) in a line scanning demonstration was achieved on glass for Si detection. For samples that are fairly temperature and vacuum stable, this approach allows the signal enhancement to be used in mapping applications.