KAIST, Electrochemistry Kwang-Seok Yun, Hong-Jeong Kim, Segyeong Joo, Juhyoun Kwak, and Euisik Yoon, "Analysis of Heavy-Metal-Ions Using Mercury Microelectrodes and a Solid-State Reference Electrodes on a Si Wafer," Jpn. J. Appl. Phys., 39 (12B) 7159 - 7163 (2000.12.__.)

Abstract
Micro working electrodes and a solid-state reference electrode have been fabricated using semiconductor processes for electrochemical detection of heavy-metal-ions in aqueous media. The working electrodes are mercury-coated platinum microelectrodes and the sizes are 5 mm, 10 mm and 25 mm in diameter. The smaller electrode shows the higher sensitivity and the detection limits of 5 mm diameter electrodes are about 0.2ppb and 0.4ppb for cadmium and lead ions, respectively. The reference electrode is Ag/AgCl electrode coated by PVC/Nafion layer containing Cl- ions. The potential variation of the fabricated solid-state reference electrodes is about 55mV under the 0.1M Cl- concentration.

Keywords : microelectrode, solid-state reference electrode, heavy-metal-ion, stripping voltammetry, SWASV, mercury electrode, microfabrication