为了达到快速、在线监测水质指标化学需氧量(COD)的目的,首次以废弃物核桃绿皮为碳源、乙二胺为氮源,水热法制备得到绿色碳点,并利用紫外可见光谱、荧光光谱及透射电镜对碳点进行了表征。基于高锰酸根内滤光效应及氧化作用猝灭碳点荧光的机理,建立了流动注射荧光猝灭法快速、自动测定水样中COD的方法。在最佳条件下,测定COD的线性范围为 0.5~80 mg/L,检出限为0.15 mg/L,Cl^-质量浓度至10 000 mg/L时不干扰测定。最后,采用该方法测定了几种环境水样的COD,结果与国标法一致。

In order to monitor chemical oxygen demand (COD) rapidly and online,green carbon dots are prepared via hydrothermal method using walnut green husk as carbon source and ethylenediamine as nitrogen source.The prepared carbon dots are characterized by ultraviolet-visible,fluorescence and transmission electron microscopy.Based on the internal filter effect of permanganate and the mechanism of carbon dots fluorescence quenching by oxidation,a fast and automatic method for the determination of COD in water samples by flow injection fluorescence quenching is established.Under the optimal conditions,the linear range for the determination of COD is 0.5-80 mg·L^-1,and the detection limit is 0.15 mg·L^-1.Cl^- with a mass concentration of 10 000 mg·L^-1 does not interfere the determination.This method is applied to determine COD in several environmental water samples,and the results obtained are consistent with those by China's national standard method.

张徐燕(1996-),女,硕士生