Open Access

ARTICLE

Bismuth Silver Sulfide (AgBiS₂) Nanoparticle-Modified SPEs Enabling Concurrent Lead and Cadmium Analysis

Wenwen Zhang^*, Changgui Lei

College of Food and Chemical Engineering, Henan Quality Institute, Pingdingshan, 467000, China

* Corresponding Author: Wenwen Zhang. Email:

Chalcogenide Letters 2025, 22(12), 1031-1045. https://doi.org/10.15251/CL.2025.2212.1031

Accepted 23 September 2025; Issue published 08 December 2025

Abstract

The development of quick, accurate, and field-deployable detection techniques is required due to the growing environmental pollution caused by heavy metals, especially lead (Pb) and cadmium (Cd). In this work, bismuth silver sulfide (AgBiS₂) nanoparticles are synthesized using a simple hydrothermal method aided by biomolecules, and they are used as a new modifier forPb(II) and Cd(II) simultaneous electrochemical detection using screen-printed electrodes (SPEs). After thorough material characterisation, pure, highly crystalline, quasi-spherical AgBiS₂ nanoparticles produced with an average diameter of around 20 nm. The AgBiS₂/SPE sensor demonstrated a threefold decrease in charge transfer resistance, indicating a considerable improvement in electrochemical performance. The sensor showed outstanding analytical performance under optimal SWASV, or square wave anodic stripping voltammetry conditions, with broad linear ranges and low 0.21 µg/L for Pb(II) and 0.15 µg/L for Cd(II) are the detection limits, both of which are far below WHO recommendations. Along with demonstrating great selectivity, good repeatability, and long-term stability,The sensor was successfully used to analyze real water samples, highlighting its promise as an affordable and reliable instrument for on-site environmental monitoring.

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Keywords

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