Construction Of Carbon Cloth-based Disposable Working Electrode And Electrochemical Device For Rapid Detection Of Heavy Metal Ions On Site

The contamination of heavy metals ions?HMIs?has become a matter for public concern in environmental issue,especially Cd²⁺and Pb²⁺,which can result in serious injury to public health even in a very low level.Electrochemical method has been considered as an efficient method in detection of HMIs because of its fast detection speed,favorable stability,easy to use,and low cost compared with absorption spectrometry and atomic fluorescence spectrometry.In traditional electrochemical analysis,the working electrode?mostly glassy carbon electrode,GCE?are often fragile and can be easily contaminated during electrochemical detection.And the GCE often require electrode polishing or electrochemical pretreatment before modification,and can only be performed for few number of tests at one time under laboratory condition,which is extremely disadvantageous and complicated for on-site monitoring in a wide range of water bodies such as oceans and lakes.Therefore,it is necessary to design a more approachable,available and effective electrode instead of GCE for field testing.In response to the above problems,we replaced the traditional GCE with carbon cloth?CC?and devoted ourselves to the development of new portable electrochemical sensors.At the same time,we developed disposable electrochemical sensors for the actual detection of water bodies.The specific research content is as follows:1. A new type of disposable carbon cloth working electrode?CCE?,which was fabricated in large scale only through simple pretreatment without complex modification,and used for on-site detection of heavy metal ions Cd²⁺and Pb²⁺by differential pulse anodic stripping voltammetry?DPASV?.The portable electrodes showed a wide detection range and the low detection limits,as well as the successful application for the simultaneous detection of Cd²⁺and Pb²⁺in real samples without interference from other ions.Better yet,the novel disposable electrode exhibited unique advantages of convenience,portability,reliability,low-cost and potential of mass production compared to conventional GCE,which may be an alternative advantageous choice for practical on-site detection of HMIs.2. In order to further improve the detection performance of carbon cloth,we prepared a new type of Fe/Fe₂O₃ package with excellent properties and packaged it into a disposable carbon cloth?ae-Fe/Fe₂O₃@CC?for the detection of Cd²⁺and Pb²⁺through new structure adjustment and surface functionalization strategy.The morphological and structural characteristics of the as-fabricated ae-Fe/Fe₂O₃@CC architecture are systematically investigated by using various characterization techniques.Through hydrothermal,calcination,acid etching and electrochemical exfoliation processes,the layered porous structure of CC can be easily established,which provides a high activity specific surface area and rapid ion diffusion rate for detection.With these remarkable features,the prepared ae-Fe/Fe₂O₃@CC achieves efficient electrochemical detection performance for Pb²⁺and3. Based on carbon cloth,a novel electrochemical carbon cloth analysis device?e CAD? is prepared.The device was assembled using a single-step functional CC as both the sensing and the substrate material.Owing to the prominent electrochemical activity of CC and the rational construction design of the device,the e CAD exhibits an excellent sensing response for Pb²⁺.In addition,a homemade-designed mini-potentiostat?MP?was combined with this e CAD to build a complete electrochemical sensing system as a simple and effective alternative for the traditional desktop commercial instruments,which can be used for field detection and signal reading directly.This study proposes an electroanalytical devices using CC for the integration of sensing and substrate functions,which is highlighted as a new generation of electrode platform for the development of portable analysis device.Based on the flexible CC,we have designed a new type of disposable e CAD,modified high-efficiency electrode,and designed a new type of electrochemical carbon cloth analysis device to build an efficient,disposable,electrochemical sensor suitable for the detetion of HIMs in field.This study provides a new choice for the detection platform of electrochemical sensors in actual water samples,and has remarkable application value and development potential.