Pbs‐field‐effect‐transistor for heavy metal concentration monitoring

Abstract

Abstract A simple and inexpensive Pbs‐FET with high sensitivity and short response time was developed which consists of a PbS layer on a pH‐sensitive gate of a field effect transistor. The PbS‐layer was prepared with simple wet precipitations technique. The PbS‐FET has about the same selectivities for Pb 2+ ‐and for Cu 2+ ‐ions, but only slight sensitivity for Cd 2+ ‐and Zn 2+ ‐ions. The sensor was integrated in a FIA system. By variing the injection time the measuring range varied between 10 −1 ‐10 −6 and 10 −2 ‐10 −8 mol Pb 2+ /1. The PbS‐FET‐FIA system is suitable for monitoring of Pb 2+ concentrations in drinking water.