3D microelectrode based on integrated micro and nano architectures

In this paper, a novel three-dimensional (3D) microelectrode integrated with micro and nano architectures has been developed to enhance the property of amperometric microsensor. By silicon bulk micromachining technology, a 3D micrometer-scale pyramidal micropool array (PMA) has been fabricated on working electrode surface. The PMA redistributes electric field strength over working electrode surface. The disequilibrium of electric field makes more porous metallic nanoparticles (NPs) clusters with large effective surface electrodeposited at micropool fringe, where the electric field is stronger. The proposed PMA can be applied for many metallic NPs to improve the microelectrode surface modification. Plantium nanoparticles (PtNPs) have been modified on PMA in this work. The results demonstrate that, the effective surface of PtNPs/PMA microelectrode is enlarged by about 40-fold than that of the planar microelectrode (PME). Compared with PtNPs-modified PME, PtNPs/PMA microelectrode has higher response current and 6-fold sensitivity for hydrogen peroxide (H₂O₂).