Photoactive titanium dioxide films with embedded gold nanoparticles for quantitative determination of mercury traces in humic matter-containing freshwaters
| Autor: | Anna Mutschler, Mika Lindén, Kerstin Leopold, Vivian Stock |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
sampling stick
General Chemical Engineering Inorganic chemistry Fluorescence spectrometry chemistry.chemical_element 02 engineering and technology 01 natural sciences Article lcsh:Chemistry chemistry.chemical_compound humic matter mercury trace analysis General Materials Science Sample preparation ddc:530 freshwater Detection limit DDC 530 / Physics Fresh water 010401 analytical chemistry Dipstick 021001 nanoscience & nanotechnology 0104 chemical sciences Mercury (element) lcsh:QD1-999 chemistry Colloidal gold gold nanoparticles Titanium dioxide Photocatalysis mesoporous titanium dioxide films Nanoparticles 0210 nano-technology |
| Zdroj: | Nanomaterials Volume 11 Issue 2 Nanomaterials, Vol 11, Iss 512, p 512 (2021) |
| Popis: | Mercury detection in humic matter-containing natural waters is often associated with environmental harmful substances for sample preparation. Herein we report an approach based on photoactive titanium dioxide films with embedded gold nanoparticles (AuNP@TiO2 dipstick) for chemical-free sample preparation and mercury preconcentration. For this purpose, AuNPs are immobilized onto a silicon wafer and further covered with a thin photoactive titanium dioxide layer. The AuNPs allow the preconcentration of Hg traces via amalgamation, while TiO2 acts as a protective layer and, at the same time, as a photocatalyst for UV-C radiation-based sample pretreatment. Humic matter, often present in natural waters, forms stabile complexes with Hg and so hinders its preconcentration prior to detection, causing a minor recovery. This problem is solved here by irradiation during Hg preconcentration onto the photoactive dipstick, resulting in a limit of detection as low as 0.137 ng L−1 using atomic fluorescence spectrometry (AFS). A 5 min preconcentration step is sufficient to obtain successful recovery of Hg traces from waters with up to 10 mg L−1 DOC. The feasibility of the approach was demonstrated by the determination of Hg traces in Danube river water. The results show no significant differences in comparison with standard cold vapor-atomic fluorescence spectrometry (CV-AFS) measurements of the same sample. Hence, this new AuNP@TiO2 dipstick provides a single-step sample preparation and preconcentration approach that combines sustainability with high analytical sensitivity and accuracy. publishedVersion |
| Databáze: | OpenAIRE |
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