Synthesis, characterization, and application of ZnO@SiO2-APTES core-shell composite for selective electrochemical detection of Pb2+ ions

• Published in: Sensors and actuators. A. Physical. 2024-08, Vol.373, p.115416, Article 115416
• Main Authors: Dhaffouli, Afef, Salazar-Carballo, Pedro A., Mabrouk, Chama, Carinelli, Soledad, Holzinger, Michael, Barhoumi, Houcine
• Format: Article
• Language: English
• Subjects: Chemical Sciences; Differential pulse voltammetry; Electrochemical sensors; Heavy metal detection; Lead; ZnO@SiO; ZnO@SiO₂-APTES
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2024.115416

This study focuses on improving the electrochemical performances for the detection of heavy metals such as Pb2+ by using a silica-based nanomaterial. In order to do this, ZnO nanoparticles (core) were used as a seed for the chemical deposition of a SiO2 shell. The nanomaterial was synthesized according to a core-shell configuration and the obtained particles were subsequently functionalized with (3-aminopropyl) triethoxysilane APTES to enhance their electrochemical sensing capabilities. The unique physical and chemical properties of these particles, such as their uniform porosity and their ability to detect Pb2+, were exploited. The resulting composite was characterized by scanning electron microscopy, X-ray diffraction, and infrared spectroscopy to analyze its morphology and chemical composition. An electrochemical characterization was also performed to evaluate the change in electrode properties with a ZnO@SiO2-APTES-modified glassy carbon electrode. The differential pulse voltammetry technique was used to determine the Pb2+ ion concentration. After optimization, the electrochemical sensor based on ZnO@SiO2-APTES showed significant sensitivity and exceptional performance in the detection of Pb2+ with a limit of detection of 0.1 nM. Moreover, the proposed electrochemical sensor was successfully applied in the determination of trace metal ions in real environmental samples. [Display omitted] •ZnO@SiO2-APTES composite was successfully synthetized.•APTES-amplified amino groups enable low-concentration Pb2+ detection.•Sensor remains robust in the presence of high metal ion concentrations.•Consistent 74 %-100 % recovery rates in complex environmental samples were obtained.