Integrated Laser-Induced breakdown spectroscopy with electroanalysis unitizing Bi2O3/Irradiated attapulgite composite for Ultra-trace detection of cadmium ions in real sample

Abstract

Refactory cadmium ion by continuous accumulation produces a severe threat to human health. It is rather important to early find Cd2+ through an effective method. However, the detection of Cd2+ using laser-induced breakdown spectroscopy (LIBS) or electroanalysis is still faced with many difficulties, such as ultra-trace detection, higher sensitive and very little metal of solid substrate. Herein, we reported a ultra-trace and sensitive detection of Cd2+ based on Bi2O340/irradiated attapulgite (IAP) composite by combining electroanalysis with LIBS. The attapulgite was irradiated with high energy ion beam by optimization. The proposed material was applied to accumulate and detect Cd2+ ion using LIBS by electrodeposition (accumulation of negative potential) and electro-adsorption (accumulation of positive potential), especially the accumulation sample was directly detected on the surface of electrode, and thus the limits of detection (LOD) was reduced in comparison with usual method, and the corresponding LOD by electrodeposition and electro-adsorption using LIBS reached 8 and 16 pM, respectively. And the LOD obtained by stripping method was 3 nM. Next, X-ray photoelectron spectroscopy was employed to further analyze the interaction mechanism. The interference has not been found. The proposed method was also applied for the detection of Cd2+ in a real sample. This study indicated that the technique combining electroanalysis with LIBS provided a novel method for the effective detection of other toxic ions.