A new approach to extraction and preconcentration of Ce(III) from aqueous solutions using magnetic reduced graphene oxide decorated with thioglycolic-acid-capped CdTe QDs

摘要

In the present study, a nanocomposite consisting of magnetic reduced graphene oxide decorated with thioglycolic-acid-capped CdTe quantum dots (TGA/CdTe QDs/Fe3O4/rGO) was synthesised using simple 'hydrothermal method' and applied as a nanosorbent for extraction and preconcentration of cerium (Ce)(III) from aqueous solutions prior to inductively coupled plasma-optical emission spectroscopy detection. Under the optimised extraction conditions, the calibration graph for Ce(III) was linear in a concentration range of 0.1-511.0 mu g L-1 with a correlation coefficient of 0.9986. A detection limit of 0.1 mu g L-1 Ce(III) with an enrichment factor of 125 was obtained. Precisions, expressed as relative standard deviation for single-sorbent repeatability and sorbent-to-sorbent reproducibility, were 3.6% and 9.1% (n = 5), respectively. Finally, spiked sea, mineral and tap waters were analysed to evaluate the performance of the proposed method. The high recoveries indicated that the suggested protocol was acceptable for determination of Ce(III) ions in the water samples. The use of QDs and study of their ability for preconcentration of metal ions is an important achievement towards designing novel adsorbents with high efficiency.