碳量子点的合成及对水体中Cr(Ⅵ)的测定

Synthesis of Carbon Dots and Determination of Cr(Ⅵ) in Water

以姜粉为碳源,通过一步水热法合成了水溶性碳量子点(CDs),通过荧光、紫外和红外光谱、荧光寿命对其发光特性进行了研究。实验发现,在pH为2.21时,Cr(Ⅵ)能使该CDs荧光强烈猝灭,提出了以姜粉CDs为荧光探针测定Cr(Ⅵ)的新方法。Cr(Ⅵ)在1.0×10^(-6)~1.0×10^(-4)mol/L范围内与荧光猝灭值ΔF线性关系良好,方法检出限为5.0×10^(-7)mol/L,RSD=0.85%(n=5,c=2.5×10^(-5)mol/L)。采用该方法测定了水样中Cr(Ⅵ)的含量,结果满意。对CDs和Cr(Ⅵ)间的猝灭机理进行了研究。

Taking ginger powder as carbon source,one-step hydrothermal method was used to synthesize water-soluble carbon dots(CDs).Fluorescence spectra,UV and infrared spectra and fluorescence lifetime were used to study the luminescent properties of the CDs.The experiments showed that in the pH=2.21 buffer solution,the fluorescence intensity of the CDs could be quenched by Cr(Ⅵ)obviously and a new method for the determination of Cr(Ⅵ)was established by using CDs as a probe.Cr(Ⅵ)solution showed a good linear relationship withΔF in the range of 1.0×10-6~1.0×10-4 mol/L,the detection limit was 5.0×10-7 mol/L,RSD=0.85%(n=5,c=2.5×10-5 mol/L).The method was applied to determine Cr(Ⅵ)in water samples with satisfactory results.The quenching process between Cr(Ⅵ)and the CDs was determined.