Fabrication of a novel low-cost sillar-modified carbon paste electrode for inorganic arsenic detection in aqueous solutions by square-wave anodic stripping voltammetry

Rodriguez Salazar O.R.; Garcia Quispe E.N.; Valdivia Portugal C.; Sosa Pulcha S.E.; Jimenez Pacheco H.G. · Results in Surfaces and Interfaces (2026) · DOI: 10.1016/j.rsurfi.2026.100983

Resumen

In recent years, analytical electrochemical techniques have gained increasing interest for the detection of heavy metals such as arsenic, lead, cadmium, mercury, among others. Research in this field has involved several studies exploring different working electrode materials, where the majority involve noble metals such as gold, while others aim to evaluate the feasibility of carbon-based modified electrodes. The present research aimed to study the development and characterization of a novel low-cost carbon paste electrode modified with iron oxides and sillar rock, a regional volcanic rock that contains noble metals in its matrix, for the detection of As(III) by Square-Wave Anodic Stripping Voltammetry. The iron–sillar modified electrode showed a strong response toward the detection of As(III) in aqueous synthetic solutions using electrochemical parameters consisting of a deposition potential of −1.0 V, a deposition time of 180 s, and an acetate buffer solution (0.5 mol L−1) at pH 5.0 as the supporting electrolyte. The study achieved a good linear response in the range of 2–10 μg L−1 of As(III), with a detection limit of 0.14 μg L−1. Copyright

Instituciones: Universidad Católica de Santa María