离子色谱法测定石墨烯中水溶性阴离子含量

Determination of water-soluble anions content in graphene powder by ion chromatography

建立石墨烯粉体中氟离子(F^(-))、氯离子(Cl^(-))、亚硝酸根离子(NO_(2)^(-))、溴离子(Br^(-))、硝酸根离子(NO_(3)^(-))、硫酸根离子(SO_(4)^(2-))和磷酸根离子(PO_(4)^(3-))的离子色谱分析方法。石墨烯样品冷冻研磨后,加入超纯水超声提取,过0.22μm聚醚砜滤膜,以IonPac AS11-HC阴离子色谱柱进行分离,8~40.0 mmol/L KOH淋洗液梯度洗脱,采用电导检测器检测,外标法定量。结果表明,7种阴离子的峰面积与其质量浓度在一定范围内呈现良好的线性关系,检出限和定量限分别为0.001~0.06 mg/L和0.003~0.198 mg/L,相对标准偏差为0.5%~5.7%(n=6),回收率在94.0%~104.0%之间。

An ion chromatography method was developed to detect F^(-),Cl^(-),NO_(2)^(-),Br^(-),NO_(3)^(-),SO_(4)^(2-),PO_(4)^(3-)in graphene powder.Sample was dispersed in ultrapure water extracted ultrasonically after freezing grind.After extraction,two milliliter of the solution was filtered with a 0.22μm polyethersulfone filter.IonPac AS11-HC was selected as the separation column,8-40.0 mmol/L KOH solutions were used as the mobile phase in gradient elution.The constituents of sample were analyzed by a conductivity detector,and quantified by external standard method.The method showed that the peak areas of the 7 anion components presented a good linear relationship in definite range of mass concentration.The limits of detection and quantification were 0.001-0.06 mg/L and 0.003-0.198 mg/L,respectively.The recoveries of this method were in the range of 94.0%to 104.0%,with relative standard deviations ranging from 0.5%to 5.7%(n=6).