Microelectrochemical Systems on Silicon Chips for the Detection of Pollutants in Seawater

Abstract

Abstract The ever‐growing demand for simple, fast and reliable techniques for the detection of pollutants and contaminants in the environment has sparked the development of remote detection and monitoring systems which include application specific sensors, instrumentation and signal processing. We report here the design, fabrication and characterisation of four designs of microelectrochemical systems on silicon chip for the detection of pollutants in artificial seawater. These systems were fabricated by photolithography and incorporate a Pt working microelectrode array (squares or bands), a Pt counter electrode and a Ag|AgCl reference electrode. They have been characterised by cyclic voltammetry of ferricyanide and behaved in good agreement with the theory. These systems were evaluated over 72 hours and showed good stability. Underpotential Deposition – Stripping Voltammetry experiments of Cu 2+ in artificial seawater have been carried out at an array of 35 microsquares of 20 µm × 20 µm. The sensitivity achieved was (2.93±0.14) µA cm −2 µM −1 , with 1 µM being the lowest Cu 2+ concentration measured. These devices provide the basis for the development into sensor systems for remote analysis applications.