Performance investigation of pre-ablation and reheating orthogonal double-pulse nanoparticle enhanced laser-induced breakdown spectroscopy

In this study, we propose a approach that nanoparticles enhanced double-pulse laser-induced breakdown spectroscopy (DP-LIBS). We also compare the effects of nanoparticles on pre-ablation and reheating orthogonal DP-LIBS. The aim is to improve the sensitivity, signal-to-noise ratio (SNR), and repeatability of LIBS emission spectra, which are inadequate for detecting of complex matrix samples. Gold nanoparticles (AuNPs) are synthesized chemically. The spacing between particles,which significantly influences spectral enhancement, is controlled by adjusting the AuNPs solution concentration applied to the Al surface. The optimal concentration is determined to be 0.168 mg/ml. We examined the impact of laser pulse energy, the interval delay time between two laser pulses, and detector gate delay time on the enhancement effect. Under optimum conditions, The SNR and Relative Standard Deviation (RSD) of both DP-NELIBS and DP-LIBS are Evaluated. Our findings real that reheating DP-LIBS, in the presence of AuNPs, results in a 1.5-fold to 3-fold increase in enhancement effects, and a 29% improvement in SNR. However, the presence of NPs in the pre-ablation structure slightly reduces performance. Overall, reheating DP-NELIBS can enhance sensitivity and lower detection limits through nanoparticle methods, thereby improving the accuracy of complex matrix samples.