Efficient and Selective Arsine Evolution Reaction on the VS_4-x-Modified Electrode for Atomic Spectroscopic...

Atomic spectroscopy technology is the gold standard for quantifying heavy metal elements; however, challenges persist in identifying element forms due to the mechanism of spectral line generation. Herein, we proposed an electrolytic hydride generation sample introduction analysis strategy for trace amounts of arsenite in complex matrices. The new method involved in situ hydrothermal preparation of a radial growth VS_4-x-coating electrode and an efficient arsine evolution reaction. It not only realized the selective separation and gaseous introduction of trivalent arsenic (As^III) at the sub-ppb level (0.1-70 μg/L) but also maintained a comparable precision to traditional chemical hydride generation methods (3.1%, n = 11). Systematic testing and theoretical calculation have shown that low adsorption energy and appropriate catalytic activity were the key to the high conversion and anti-interference ability of the VS_4-x electrode, while the long-term stability and low memory effect provided an effective guarantee for practical application. The value of this study is not only to provide an economic and sustainable spectral introduction method for the accurate analysis of highly toxic arsenite but also to provide a new phase interface perspective for the study of the hydride generation mechanism.