以铁观音茶叶为原料,使用水热法合成发蓝色荧光的碳量子点(CQDs),采用透射电镜对其形貌进行表征,通过紫外-可见吸收光谱、荧光光谱对其发光性能进行研究。将合成的CQDs作为荧光探针用于水体中Cr6+离子的检测,探讨了pH、反应时间对Cr6+离子检测的影响。结果表明:在最优检测条件下,CQDs的荧光猝灭率与Cr6+离子浓度呈现良好的线性关系,检测的线性范围为2.0～9.0μmol/L,检测限为0.15μmol/L,加标回收率为94%～102%。该法具有高灵敏度、高准确性,对Cr6+离子的检测取得了较好的效果。
Tieguanyin tea was used as raw material to synthesize blue fluorescent carbon quantum dots (CQDs) by hydrothermal method.The morphology of CQDs was characterized by transmission electron microscopy.The luminescence properties of CQDs were studied by UV-Vis absorption spectra and fluorescence spectra.The effects of pH and reaction time were investigated for the detection of Cr6+ ions in water.Under the optimal detection conditions,the results showed that the fluorescence quenching rate of CQDS showed a good linear relationship with the concentration of Cr6+ ions.The linear range of detection was 2.0～9.0μmol/L,the detection limit was 0.15μmol/L,and the spiked recovery rate was 94% to 102%.The method has achieved good results with high sensitivity and accuracy for the detection of Cr6+ ions.
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