Laser induced plasmas at different nebulization conditions: Spatio-temporal distribution of emission signals and excitation temperatures

Nebulization assisted molecular LIBS for sensitive and fast fluorine determination in aqueous solutions

“…A delay of 30 μs with an integration time of 5 μs was selected due to the high CaF emission at a relatively short integration time, avoiding the greater RSDs observed at longer delay times. This behaviour of signal uncertainty can be linked to a previous work regarding nebulization-modified LIBS, 17 which showed increasing instabilities with longer delay times (ten microseconds onwards) of the plasma plume under a Ca-solution nebulization, as compared to a non-nebulized plume. Fig.…”

“…Particularly, it has been shown that these morphology fluctuations increase with delay time in general. 19 In addition, it has also been observed in a previous work 17 that the nebulization affects several parameters of the plasma plume including shape variability. Another source of uncertainty, which could explain the increased RSDs of some points in the calibrations, could be due to occasional undetected malfunction of the nebulizer.…”

“…It has been shown that droplets deposited on the surface of a metal solid can produce an increase in ablation rate, even for small aerosol droplets, 20 and this effect has also been observed in nebulization experiments with a solid copper target. 17 If the glycerin content is enough to increase the size of the accumulated droplets and a greater amount of pellet is ablated, the relative amount of clean bulk matter will be increased (since F is just at the most superficial layer of the pellet) and greater emission from the CaO/CaOH molecules will be expected. In such a case, since CaF emission is maintained, the normalization procedure to a now-higher signal of CaO/CaOH would be translated into an underestimated determination of CaF.…”

“…The main instrumental of the nebulization-assisted LIBS experimental set-up has been shown in an earlier work 17 and it's described below.…”

Atomic spectrometry update: review of advances in atomic spectrometry and related techniques

“…In the case of Ca-free samples, the simultaneous nebulisation of a Ca-containing solution during LIBS analysis can be used to achieve a CaF molecular emission that is proportional to the amount of F in the sample. Méndez-López et al 105 investigated these interactions between the nebulised solution and the plasma for different nebulisation conditions, using Cu as a model substrate sample. When a solution of Ca was nebulised the decay intensity of the Cu lines changed, with lower average Cu T exc and increased ablation rates.…”