摘要
利用锆金属有机骨架(UiO-66)与半导体石墨相氮化碳(g-C_(3)N_(4))复合可形成异质结结构,构建了一种基于g-C_(3)N_(4)-UiO-66复合物修饰电极的电化学发光传感器用于水中污染物邻苯二酚的检测。分别合成g-C_(3)N_(4)和UiO-66,将二者充分研磨、煅烧后,得到g-C_(3)N_(4)-UiO-66复合物。以N,N-二甲基甲酰胺为溶剂配制1.0 g·L^(-1)的g-C_(3)N_(4)-UiO-66分散液,分取3.0μL,用滴涂的方式修饰到处理好的玻碳电极(GCE)表面,自然晾干后,得到g-C_(3)N_(4)-UiO-66修饰的GCE(g-C_(3)N_(4)-UiO-66@GCE)。以g-C_(3)N_(4)-UiO-66@GCE为工作电极,铂丝为辅助电极,Ag/AgCl为参比电极,将该三电极系统置于含有50 mmol·L^(-1) K_(2)S_(2)O_(8)的磷酸盐缓冲溶液(pH 7.5)中,采用循环伏安法在-1.6~0 V内,以0.1 V·s^(-1)速率进行扫描,记录加入邻苯二酚前后体系的电化学发光强度差值,即猝灭值。结果表明:体系电化学发光强度猝灭值与邻苯二酚浓度的对数呈线性关系,线性范围为1.0×10^(-5)~5.0×10^(-2)μmol·L^(-1),检出限为9.0×10^(-12)mol·L^(-1);用6根g-C_(3)N_(4)-UiO-66@GCE进行重现性试验,6次测定值的相对标准偏差(RSD)为3.3%;按照测试条件在-1.6~0 V内连续循环扫描31次,结果显示,加入邻苯二酚前后,测定值的RSD均小于4.0%;并且该传感器对对苯二酚、间苯二酚、葡萄糖、Na^(+)、K^(+)等干扰物质具有较好的抗干扰能力;用此电化学发光传感器分析自来水样品并进行加标回收试验,结果未检出邻苯二酚,回收率为98.4%,测定值的RSD(n=5)为3.8%。
An electrochemiluminescence sensor for the determination of catechol pollutant in water was constructed based on modified electrode with g-C_(3)N_(4)-UiO-66 composite by heterojunction structure formed with zirconium metal-organic frameworks(UiO-66) and semiconductor graphite phase carbon nitride(g-C_(3)N_(4)).The g-C_(3)N_(4) and UiO-66 were synthesized,and after the matericals were fully ground and calcined,g-C_(3)N_(4)-UiO-66 composite was obtained.The 1.0 g·L^(-1) g-C_(3)N_(4)-UiO-66 dispersion was prepared with N,N-dimethylformamide as solvent,and an aliquot(3.0 μL) was dripped onto the surface of pretreated glassy carbon electrode(GCE).After natural drying,the modified GCE with g-C_(3)N_(4)-UiO-66(g-C_(3)N_(4)-UiO-66@GCE) was obtained.The three-electrode system with g-C_(3)N_(4)-UiO-66@GCE as the working electrode,platinum wire as the auxiliary electrode and Ag/AgCl as the reference electrode was placed into the phosphate buffer solution(pH 7.5) containing 50 mmol·L^(-1) K_(2)S_(2)O_8,and the difference of electrochemiluminescence intensity of the system(quenching value) was recorded before and after adding catechol by cyclic voltammetry in the range of-1.6-0 V at scanning speed of 0.1 V ·s^(-1).As shown by the results,there was a linear relationship between the quenching value of electrochemiluminescence intensity and the logarithm of catechol concentration,and the linear range was 1.0 ×10^(-5)-5.0 ×10^(-2) μmol·L^(-1),with detection limit of 9.0×10^(-12)mol·L^(-1).The six g-C_(3)N_(4)-UiO-66@GCE was used for reproducibility test,and RSD of the six determined values was 3.3%.According to the test conditions,31 cycles were continuously scanned in the range of-1.6-0 V,which showed that RSDs of the determined values were less than 4.0% before and after adding catechol.The sensor had good anti-interference ability to the interfering substances,including hydroquinone,resorcin,glucose,Na~+ and K~+.The tap water sample was analyzed with the electrochemiluminescence sensor,and the test for recovery was made by standard addition.The results showed that catechol was not detected,and the recovery was 98.4%,with RSD(n=5) of the determined values of 3.8%.
作者
王国宇
单晓梦
椎木弘
WANG Guoyu;SHAN Xiaomeng;HIROSHI Shiigi(Changzhou University,Changzhou 213164,China;Osaka Prefecture University,Osaka 599-8531,Japan)
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2023年第4期380-386,共7页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
基金
常州市科技计划项目(CQ20204033)。
