A novel disk-arc arrayed electrochemical sensor

In this paper, a novel-structured electrochemical sensor array with five disk working electrodes, one arc counter electrode and one reference electrode is introduced. The array is fabricated by micro-electro-mechanical system (MEMS) technology. The radii of the disk working electrodes are 400 μm and 500 μm while the distance between the working electrodes and counting electrode is 100 μm. The counter electrode is composed of difference arc rings. The radian of the arc rings ranges from n to μm while the radius ranges from 100 μm to μm for different chips. The arrays are characterized by cyclic voltammetry in the presence of the redox probe ferrocenemethanol (FcM). It is found that the peak current has a biggest value between 3π/2 and 5π/3 at the same radius of arc rings. The peak current increases along with the increasing of the radius of the arc rings. For working electrode in same size, the best design has the peak current 35% higher than the smallest peak current. An optimal design of the high sensitivity electrochemical sensor is found.