Improvement in signal sensitivity and repeatability using copper nanoparticle-enhanced laser-induced breakdown spectroscopy

In the present work, the sensitivity and repeatability of the emission spectra have been investigated using nano-enhanced laser-induced breakdown spectroscopy (NELIBS). The colloidal solution of copper nanoparticles was produced by using the laser ablation technique at the fundamental wavelength of Nd: YAG laser at 100 mJ and deposited on the surface of standard aluminum alloy in different concentrations. With varying laser irradiances (10 GW/cm2 to 35 GW/cm2) and nanoparticles surface concentration (6.4 μL/cm2 to 57.7 μL/cm2), emission spectra were acquired from laser-induced plasma. On average the signal enhancement up to 50 times was achieved at a laser irradiance of 28.3 GW/cm2 and at NPs concentration of 45 μL/cm2. A decrease in relative standard deviations (RSD) from 28% to 16% for manganese and 18% to 10% for aluminum emission lines was achieved at laser irradiance of 10.5 GW/cm2 and surface concentration of 19.2 μL/cm2.