Calibration-Free Laser-Induced Plasma Analysis of Nanoparticle-Doped Material Using Self-Absorption Correction Methodologies

Appl Spectrosc. 2019 Jan;73(1):30-39. doi: 10.1177/0003702818789959. Epub 2018 Oct 23.

Abstract

The qualitative and quantitative analysis of doped nanomaterial containing iron (Fe) and tin (Sn) nanoparticles was investigated using laser-induced breakdown spectroscopy (LIBS). Doped nanoparticles were prepared via co-precipitation and hydrothermal processes. The emission spectra of ablated plasma of doped material revealed the existence of different species in the doped nanomaterial. Simple calibration-free LIBS (CF-LIBS) and internal reference self-absorption correction (IRSAC) CF-LIBS approaches were applied to emission spectra of nanomaterial for quantitative analysis. For both approaches, different spectroscopic parameters such as plasma temperature and electron number density were also determined. Plasma temperature was estimated using a Boltzmann plot and Saha-Boltzmann plot while electron number density was estimated by Stark broadening methods and Saha-Boltzmann equations. Results of both calibration-free approaches were compared with a weight percentage method and other recognized techniques such as laser ablation time of flight (LA-TOF) spectroscopy and energy dispersive X-ray (EDX). We concluded that our results provide good agreement with experimental data obtained using LA-TOF spectroscopy and a small deviation from data obtained using the EDX technique. The current work confirms LIBS as a valid analytical approach for quantitative analysis of nanomaterials.

Keywords: CF-LIBS; Doped nano structures; IRSAC LIBS; LA-TOF; LIBS; ablated plasma; calibration-free LIBS; internal reference self-absorption correction; laser-ablation time-of-flight spectroscopy; laser-induced breakdown spectroscopy.