CAJ | 학술논문

基于微加工技术( Microfabrication technology)制备微传感电极并进行电化学表面修饰，研制出一种用于水体中NO-3浓度检测的电化学微传感器。微传感器以两电极传感芯片为信号转换部件，使用电流脉冲沉积法在铂质工作电极表面制备微观形貌呈枝簇状的铜质敏感材料，利用铜质材料对酸性溶液中NO-3的电催化还原特性，测量还原电流的大小，实现对NO-3浓度的检测。采用扫描电子显微镜( SEM)和X射线衍射分析( XRD)技术对敏感膜进行表征和监测，探索高活性铜质敏感膜的制备方法；使用微传感器对硝酸盐标准样品进行检测，在低浓度范围(12.5~200μmol/L)，响应灵敏度为0.1422μA/(μmol/L)；高浓度范围(200~3000μmol/L)，响应灵敏度为0.0984μA/(μmol/L)，均表现出较高的检测灵敏度；使用微传感器对北京等地的实际湖库水样进行检测，结果与专业水质检测机构采用紫外分光光度法的测试结果偏差在-3.9%~15.4%之间，两者具有一定的相关性，表明微传感器能够用于实际水样中NO-3浓度的测量。
기우미가공기술( Microfabrication technology)제비미전감전겁병진행전화학표면수식，연제출일충용우수체중NO-3농도검측적전화학미전감기。미전감기이량전겁전감심편위신호전환부건，사용전류맥충침적법재박질공작전겁표면제비미관형모정지족상적동질민감재료，이용동질재료대산성용액중NO-3적전최화환원특성，측량환원전류적대소，실현대NO-3농도적검측。채용소묘전자현미경( SEM)화X사선연사분석( XRD)기술대민감막진행표정화감측，탐색고활성동질민감막적제비방법；사용미전감기대초산염표준양품진행검측，재저농도범위(12.5~200μmol/L)，향응령민도위0.1422μA/(μmol/L)；고농도범위(200~3000μmol/L)，향응령민도위0.0984μA/(μmol/L)，균표현출교고적검측령민도；사용미전감기대북경등지적실제호고수양진행검측，결과여전업수질검측궤구채용자외분광광도법적측시결과편차재-3.9%~15.4%지간，량자구유일정적상관성，표명미전감기능구용우실제수양중NO-3농도적측량。
Based on microfabrication technology and electrochemical modification method, a micro electrochemical sensor for nitrate ( NO-3 ) determination was developed. A micro sensor chip with working electrode and counter electrode was used as the signal convertor of the sensor. The area of the micro working_electrode was only 1 mm2 . As an electrocatalysis sensitive material, copper was electrodeposited onto the working electrode by square_wave pulse current electrodeposition method. The morphologies and components of freshly deposited materials were examined by scanning electron microscopy ( SEM ) and X_ray diffraction ( XRD) to explore key factors that affected the electrocatalytic ability of the deposited copper layer for reducing nitrate ions. The experimental results revealed that under the optimal conditions, the deposited copper layer was macroporous and had a larger effective surface area that could serve as a more effective electrocatalyst in facilitating nitrate reduction. Electrochemical response of the macroporous copper layer was characterized by linear sweep voltammetry in acidic supporting electrolytes ( pH=2 ) . The electroanalytical results showed that the modified microsensor had marked sensitivity for standard nitrate samples within the concentration range from 12. 5 to 3000 μmol/L (in the range of 12. 5-200 μmol/L yielded straight line:y1=-0. 1422x-10. 326, R12=0. 9976, while in the range of 200-3000 μmol/L yielded straight line: y2=-0. 0984x-22. 144, R22=0. 9927) with a detection limit of 2 μmol/L (S/N=3). The developed electrochemical microsensor was also employed for nitrate determination in water samples collected from lakes and rivers near the city of Beijing. The results were in good agreement with the data given by qualified water quality detection institute, with the deviations from 3 . 9% to 15 . 4%.