Abstract

Heavy metal ions are not subject to biodegradation and could cause the environmental pollution of natural resources and water. Many of the heavy metals are highly toxic and dangerous to human health, even at a minimum amount. This work considered an optical method for detecting heavy metal ions using colloidal luminescent semiconductor quantum dots (QDs). Over the past decade, QDs have been used in the development of sensitive fluorescence sensors for ions of heavy metal. In this work, we combined the fluorescent properties of AgInS2/ZnS ternary QDs and the magnetism of superparamagnetic Fe3O4 nanoparticles embedded in a matrix of porous calcium carbonate microspheres for the detection of toxic ions of heavy metal: Co2+, Ni2+, and Pb2+. We demonstrate a relationship between the level of quenching of the photoluminescence of sensors under exposure to the heavy metal ions and the concentration of these ions, allowing their detection in aqueous solutions at concentrations of Co2+, Ni2+, and Pb2+ as low as ≈0.01 ppm, ≈0.1 ppm, and ≈0.01 ppm, respectively. It also has importance for application of the ability to concentrate and extract the sensor with analytes from the solution using a magnetic field.

Highlights

  • The industrial development has resulted in constantly increasing levels of heavy metal contamination in the environment [1,2]

  • We focus on the design of AgInS2 -based sensors for the most common toxic heavy metal ions, Co2+, Ni2+, and Pb2+, which can accumulate in the human body and cause acute or chronic diseases [40,41]

  • The SEM (STEM) images of CaCO3 microspheres, doped by Fe3 O4 nanoparticles, Fe3 O4 magnetic nanoparticles, and AgInS2 /ZnS quantum dots (QDs) stabilized with thioglycolic acid (TGA) are shown in Figure 1b–d, respectively

Read more

Summary

Introduction

The industrial development has resulted in constantly increasing levels of heavy metal contamination in the environment [1,2]. It is necessary to determine heavy metal ions in soil [3,4] and water resources [5,6]. The detection and selective quantitative definition of heavy metal ions in nature-conservation resources or biological samples have been an important research area for a long time. The development and creation of sensors based on nanoparticles (NPs) have experienced significant growth over the past decades [7,8,9]

Methods
Results
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call