Selective detection of Hg(II) ions from Cu(II) and Pb(II) using AlGaNGaN high electron mobility transistors

Abstract

Bare Au-gated and thioglycolic acid functionalized Au-gated AlGaNGaN high electron mobility transistors were used to detect mercury(II) and copper(II) ions. Fast detection of <5 s was achieved for thioglycolic acid functionalized sensors. The thioglycolic acid functionalization increased the sensitivity for detection of mercury by 2.5 times over the bare Au-gated surface. Both surfaces had a selectivity of approximately 100-fold over other contaminating ions of sodium, magnesium, and lead and can be easily recycled. Our results show that portable, selective, and fast Cu2+ and Hg2+ sensors can be realized by combining bare Au-gated and thioglycolic acid-functionalized surface in one sensor. © 2007 The Electrochemical Society.