一步法制备氮掺杂碳量子点及高选择性荧光检测Cr^3+

One-Step Preparation of Nitrogen-Doped Carbon Quantum Dots andHigh Selective Fluorescence Detection of Cr^3+

用L-甲硫氨酸和尿素作为前驱体,N,N-二甲基甲酰胺作溶剂,通过溶剂热法合成了一种新颖的碳量子点,并通过透射显微镜、激光粒度仪等对其结构和粒径进行表征。随后,通过紫外及荧光测试,对新合成的碳量子点对重金属离子铬的检测性能进行了研究。并探究了其对10种金属离子及空白对照的选择性,以及在干扰离子存在时的竞争性。结果表明,所合成的碳量子点粒径为3~5 nm,且粒径较为均匀。通过紫外及荧光测试分析发现,在一定浓度范围内,该量子点的荧光强度随浓度增加而增加。而在重金属离子检测方面,即使在干扰离子存在的情况下,该碳量子点仍然能较好地识别铬离子,引起量子点荧光强度的增强。因此该碳量子点对铬离子有较好的检测性能,可用作工业废水中铬离子的检测。

Using L-methionine and urea as precursors,N,N-dimethylformamide as solvent,then a novel carbon quantum dots is synthesized by solvothermal method.The structure and particle size are characterized by TEM,DLS,etc.Subsequently,through ultraviolet and fluorescence tests,the detection performance of the newly synthesized carbon quantum dots for heavy metal ions chromium,the selectivity to 10 kinds of metal ions and blank control investigated,and the competition in the presence of interfering ions are investigated.The results show that the particle size of the synthesized carbon quantum dots is about3~5 nm,and the particle size is relatively uniform.Through ultraviolet and fluorescence test analysis,it is found that within a certain concentration range,the fluorescence intensity of the quantum dots increases with the increase in concentration.For the detection of heavy metal ions,even in the presence of interfering ions,the carbon quantum dots can still better identify Cr^3+,causing enhancement of fluorescence intensity of quantum dots.Therefore,the CDs have better detection performance for Cr^3+,and can be used for the detection of Cr^3+in industrial wastewater.