许多水域含有过量的硝酸根, 会诱发许多问题。采用微机电系统工艺, 制备出一种基于铂叉指微电极阵列的硝酸根离子(NO-3)检测微传感电极。通过电化学恒电位沉积法在铂叉指微电极阵列上修饰, 得到多孔、簇状铜敏感膜。采用线性扫描伏安电化学检测方法, 考察该微传感电极对NO-3的响应性能, 在0~2 mg/L浓度范围内, 线性度为0.999, 灵敏度为-3.15 μA·L·mg-1 。在相同沉积修饰条件下, 叉指微电极比同等敏感面积(1 mm2)的圆盘微电极表现出更强的催化活性和更高的灵敏度, 分析其原因, 认为主要是叉指微电极的结构和边缘效应造成的。

Nitrate(NO-3) is widely distributed in the water environment, and induces many problems. A platinum inter-digitated array (IDA) microelectrode modified with copper clusters has been developed to enhance the performance of the electrochemical sensor for nitrate determination. The IDA microelectrode was fabricated by Micro Electro-Mechanical System (MEMS) technique. The copper clusters electrodeposited on the IDA microelectrode are porous and have large surface area. The electrochemical performance of the modified microelectrode for nitrate determination was characterized by using linear sweep voltammetry in three-electrode system. The linear range of the copper modified IDA microelectrode for nitrate (N-NO-3) determination was from 0 to 2 mg/L with a linearity of 0.999 and a sensitivity of -3.15 μA·L·mg-1. The IDA microelectrode with sensitive area of 1 mm2 possessed a higher electrocatalytic activity and superior sensitivity for nitrate determination than the disk microelectrode with indentical area due to the structure and edge effect of IDA microelectrode.