Fabrication of surface renewable carbon microelectrode arrays and their application in heavy metal ion sensing

Abstract

In this paper, surface renewable carbon microelectrode arrays (MEAs) were developed using microfabrication technology and were successfully applied in heavy metal ion sensing. The as-prepared carbon microelectrode was fabricated with a cylindrical shape 50 μm in diameter and 300 μm in height. Cyclic voltammetry (CV) analysis with scan rates ranging from 10 mV s⁻¹ to 100 mV s⁻¹ was utilized to characterize the MEAs, and it was found that the typical properties (flat redox peaks) of MEAs appeared at lower scan rates (<30 mV s⁻¹). Heavy metal ions, including Cd²⁺, Pb²⁺ and Cu²⁺ were chosen to demonstrate the performance of the developed MEAs for electrochemical sensor applications, with the detection limit calculated to be 1 μg L⁻¹. Renewability and repeatability experiments were also carried out to demonstrate the good characteristics of the MEAs. This work developed a novel microfabrication technique for low cost surface renewable MEAs that can be used as an electrochemical platform for a wide range of sensor applications.