该文设计并制备了一种多层微结构的安培型氨气三维微纳传感芯片,并构建了以此微传感芯片为敏感单元的氨氮检测系统,探索了使用安培型氨气微传感器检测氨氮的方法。该微传感芯片采用微纳加工工艺制备,使用聚合物键合工艺在较低温度下实现了微传感器多层结构的封装。使用纳米铱作为传感器的敏感材料,其具有良好的电催化氧化能力,可使传感器具有较高的灵敏度。对Ag/AgCl微参比电极的稳定性进行了考察。使用自行设计的氨氮检测系统对氨氮样品进行检测,对微传感器的时间响应特性、浓度响应特性、重复性及选择性进行了测试和分析。实验结果表明,在0.5~10 mg/L的测试范围内,检测电流与氨氮浓度保持良好的线性,灵敏度为1.62μA/(mg/L),线性相关系数为0.995,重复性偏差为5.73%。同时,传感器显示出良好的选择性。
A miniaturized multilayer 3D micro/nano ammonia sensor chip is designed and prepared.An ammonia nitrogen measurement system utilizing such a miniaturized sensor chip is constructed.The method of ammonia nitrogen measurement using a miniaturized amperometric ammonia sensor is investigated.The sensor chip is fabricated by micro/nano fabrication technology.Polymer adhesive bonding method is used to achieve the encapsulation of multilayers of the sensor under relatively low temperature condition.Nanoparticles of iridium which possessses excellent electrocatalysis is utilized to enhance the sensitivity.The stability of micro Ag/AgCl reference electrode is evaluated.Measurement of ammonia nitrogen using the self-designed measurement system is presented.The characterizations of the sensor,including relationship between response and sample concentrations,response times,reproducibility and selectivity are demonstrated.A linear calibration curve between 0.5~10 mg/L is obtained with the sensitivity of 1.62 μA/(mg/L) and the correlation coefficients of 0.995.The Relative Standard Deviation(RSD) is 5.73%.Meanwhile,the results reveal that the sensor possesses good selectivity.