Imprinted Functional Carbon Materials For The Detection And Removal Of Cupric Ion

The current situation of water shortage is aggravated by water pollution caused by the rapid development of urbanization and industrialization.The water pollution of heavy metal ions has become one of the main sources owing to their wide pollution range and difficult degradation.Among them,the existence of excessive Cu²⁺seriously threatens the environment and human health.Therefore,in order to ensure people?s drinking water safety,it is very necessary to achieve the detection and removal of Cu²⁺.At present,in the process of detecting Cu²⁺by ion imprinted electrochemical sensors,ion imprinted polymers are mixed with carbon black or graphene,which has the disadvantages of low utilization rate of materials and complicated operation.Therefore,carbon-based ion imprinted materials were used to replace graphite or carbon black.In the process of eluting Cu²⁺from ion imprinted polymers prepared by chemical method,a large amount of acid or basic reagents and organic solvents was used,which caused secondary pollution and waste.In order to solve this problem,electrochemically switched ion exchange technology was combined with ion imprinting technology to avoid contamination and waste caused by elution.The main contents and results are as follows:1.Imprinted functional carbon spheres for detecting Cu²⁺The imprinted functional carbon spheres(Cu²⁺-IIPs)were prepared on the surface of modified carbon spheres by ion imprinting technology,using Cu²⁺as template,N-propylacrylamide as functional monomer,N,N-methylene-bis-acrylamide as cross-linker and ammonium persulphate as initiator.By dispersing Cu²⁺-IIPs on glassy carbon electrode,Cu²⁺imprinted electrochemical sensor(Cu²⁺-IIPs/GCE)was obtained.The electrochemical performance of Cu²⁺-IIPs/GCE was evaluated by differential pulse voltammetry method.The current response value of Cu²⁺-IIPs/GCE was 2.14 times that of the non-imprinted electrode,suggesting Cu²⁺-IIPs/GCE has specific recognition for Cu²⁺.The response of Cu²⁺-IIPs/GCE to Cu²⁺was linear in 1.0×10^-5 to 1.0×10^-3 mol L^-1.The detection limit was 5.99×10^-6 mol L^-1?S/N=3?,showing good sensitivity.The imprinted electrochemical sensor is prepared through the facile method and the quantity of Cu²⁺-IIPs is only 0.0035 mg mm^-2,which is far less than the quality used in other reports needed to be capable of detecting Cu²⁺in water.It provides a new way for the detection of heavy metal ions.2.Carbon cloth surface imprinted functional film for removing Cu²⁺The surface imprinted functional film(Cu²⁺-IIF)was prepared by unipolar pulse electropolymerization method for removing Cu²⁺,using Cu²⁺as template,ferrocyanide ion(Fe?CN?₆^4-)as functional monomer,pyrrole as cross-linker and conductive agent,carbon cloth as carrier.Because of the doped Fe?CN?₆^4-in the film,Cu²⁺can be removed by Cu²⁺-IIF from 5 ppm to 0.5 ppm.The removal rate reaches 90%,and the direct emission level can be reached.The removal capacity of Cu²⁺-IIF is higher than that of non-imprinted film.The relative selectivity factors of Cu²⁺with respect to Cd²⁺,Zn²⁺and Ni²⁺are 49.27,26.52 and 30.16,respectively.The removal capacity of Cu²⁺-IIF remained 95.13%after five cycles.Cu²⁺-IIF shows good selectivity and reproducibility,expected to be used for selective removal of Cu²⁺at low concentrations.