Influence of substrate temperature on the detection sensitivity of surface-enhanced LIBS for analysis of heavy metal elements in water

Abstract

The current research confirms that substrate temperature plays a dominant role in improving the detection sensitivity of surface-enhanced laser-induced breakdown spectroscopy (SE-LIBS) technology. In the experiment, SE-LIBS is used to detect trace heavy metal elements in aqueous solutions. The influence of the substrate temperature on the spectral intensity of Pb and Cr is discussed. Calibration curves are constructed for Pb and Cr at different substrate temperatures. The corresponding limit of detection (LoD) is calculated. The LoDs of Pb and Cr decrease from 31.7 ng mL⁻¹ and 4.6 ng mL⁻¹ to 8.0 ng mL⁻¹ and 1.2 ng mL⁻¹ as the substrate temperature increases from 25 °C to 200 °C. Increasing the substrate temperature can further improve the analytical ability and detection sensitivity of SE-LIBS for detecting heavy metal elements. The study provides a feasible scheme for the detection of heavy metal elements in wastewater.