多壁碳纳米管掺杂的铜基金属有机框架材料银离子固态电极研究  

A Solid Electrode for Detection of Silver Ion Based on Copper-based Metal-Organic Frameworks Doped by Multi-walled Carbon Nanotubes

作　　者：张丹阳 蔡瑶 沈雨 许文菊[1] ZHANG Dan-Yang;CAI Yao;SHEN Yu;XU Wen-Ju(College of Chemistry and Chemical Engineering,Southwest University,Chongqing 400715,China)

机构地区：[1]西南大学化学化工学院,重庆400715

出　　处：《分析化学》2018年第11期1794-1801,共8页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(No.21775123);重庆市自然科学基金项目(No.cstc2018jcyjAX0214)资助~~

摘　　要：金属有机框架材料(MOFs)是由无机金属离子和有机配体形成的具有网状多孔结构的新型材料,具有比表面积大、孔隙发达、易功能化、稳定性良好等优势,已广泛应用于太阳能电池、生物药物、催化、生物传感器构建等领域。但作为敏感元件用于离子选择性电极的研究并不多。本研究以具有多孔球形的铜基金属有机框架材料(CuMOFs)为离子选择性电极的敏感载体,并掺杂具有优良导电性和大比表面积的多壁碳纳米管(MWCNTs),制备了灵敏的固态碳糊电极,用于Ag^+的分析检测。结果表明,CuMOFs载体固态电极对Ag^+呈现良好的选择性电位响应。对电极敏感膜CuMOFs和MWCNTs的构成比例和测试溶液的pH值进行了优化。当CuMOFs与MWCNTs质量比为99∶1时,固态碳糊电极在pH 2. 0的HNO_3溶液中对Ag^+呈斜率为57.9 m V/dec的近Nernst电位响应,线性范围为5.0μmol/L～0.1 mol/L,检出限为3.2μmol/L。此Ag^+固态电极选择性高,稳定性良好,电位响应快速。与已报道的其它敏感载体Ag^+电极相比,掺杂MWCNTs的CuMOFs固态碳糊电极的分析灵敏度有明显改善。将制备的碳糊电极初步应用于环境水样中Ag^+含量的测定,结果令人满意。本研究为进一步拓展其它MOFs材料在化学传感器领域的应用提供了良好的借鉴。Metal-organic framework materials(MOFs),formed by the coordination of inorganic metal ions and organic ligands,are a kind of new materials with porous network structure.MOFs possess many advantages such as a large specific surface area,developed pores,easy functionalization,and good stability.In the present,MOFs have been applied to many areas including solar batteries,biopharmaceuticals,catalysis and biosensors.But little attentions have been received on the application of MOFs as the sensing materials for analytical detection platform based on ion-selective electrodes.In this work,copper-based metal-organic frameworks(CuMOFs)with porous spherical structure were used as the sensitive carriers of ion-selective electrode,in which multi-walled carbon nanotubes(MWCNTs)with excellent conductivity and large surface area were doped.This resulted in the development of a sensitive solid carbon paste electrode for the detection of silver ion(Ag+).The experimental results demonstrated that the CuMOFs-based solid electrode had good selective potential response to Ag+.We investigated the effect of different content ratio of the sensing membrane CuMOFs and MWCNTS,and pH of the tested solution on the potential response.The obtained results suggested that the proposed solid carbon paste electrode containing CuMOFs and MWCNTs(99∶1,w/w)had the best near-Nernst potential response to Ag+in HNO 3 solution at pH 2.0,suggesting that MWCNTs was favorable for promoting the electron transfer in the electrode interface.Under the optimal experimental conditions,the widest dynamic linear range was 5.0μmol/L-0.1 mol/L with the slope of 57.9 mV/dec and the detection limit of 3.2μmol/L.This may be attributed to the effective interaction between CuMOFs and Ag+,which was proved by the UV-Vis spectra before and after CuMOFs interacted with Ag+.Furthermore,the solid ion-selective electrode displayed high selectivity for silver ions in the presence of other tested interfering ions,good stability,and fast and reversible potential response in dif

关 键 词：电位分析 铜基金属有机框架材料 固态离子选择性电极 银离子 近Nernst响应 

分 类 号：O657.1[理学—分析化学] X832[理学—化学]