Effect of liquid aerosol temperature on the detection performance of LIBS for analysis of phosphorus element in water

For analyzing the phosphorus (P) element in water, a liquid aerosol is used as a sampling method of laser-induced breakdown spectroscopy (LIBS). To further improve the detection performance of liquid aerosol-LIBS, the effect of liquid aerosol temperature on the qualitative and quantitative analysis was investigated. With increasing the liquid aerosol temperature, the emission intensity of P increased with the temperature; the threshold energy density (Eth) of P I 213.618 nm decreased from 9.98 to 6.62 J cm-2, and the optimal laser energy density reduced from 26.00 to 18.70 J cm-2. In addition, the LoD of P decreased from 5.22 to 1.81 ppm, and the average relative standard deviation (ARSD) of the intensity of P I 213.618 nm was similar. Furthermore, the R2, the average relative error (ARE), and the root mean square error of cross validation (RMSECV) were improved from 0.9926 to 0.9964, 8.93 to 5.95%, and 4.85 to 2.91 ppm. The results indicate that liquid aerosol temperature affects the sensitivity, LoD, and accuracy of liquid aerosol-LIBS for the analysis of P in water. A simple and convenient method has been developed to improve the LIBS detection performance of a liquid aerosol by adjusting the liquid aerosol temperature.