Determination of lead in gallium arsenide by graphite furnace atomic absorption spectrometry with an ammonium chloride–chromium(III) chloride chemical modifier

Abstract

A method is described for the determination of trace amounts of lead in gallium arsenide by graphite furnace atomic absorption spectrometry (GFAAS) using chemical modification. The sample is dissolved in hydrochloric acid and bromine, with the addition of ammonium chloride plus chromium(III) chloride as the chemical modifier. The ashing and atomization steps were optimized. The detection limit was found to be 5 ng g^–1 for peak height measurements and 13 ng g^–1 for peak area measurements. The reproducibility of the over-all procedure is 2–10% depending on the lead content. The results were in agreement with those obtained by anodic stripping voltammetry.