Determination of lead,tin, tellurium,and some doping elements in PbxSn1−xTe

A single method, based on gravimetric and polarographic analysis, has been developed to determine, in the same sample, the fundamental constituents and some doping elements in the Pb_xSn_1?xTe system. First tellurium is separated by sulfur dioxide in an acid solution (5% in HCl). This medium is suitable both for the total tellurium separation and for the subsequent tin precipitation by phenylarsonic acid. Moreover, this analytical procedure allows determination in the same sample, the concentration of some doping elements such as copper, cadmium, and zinc which are necessary to vary some physical properties of the Pb_xSn_1?xTe semiconductor system. The trace elements were determined by stripping voltammetry after tellurium, tin, and lead separation. The residual solution contains a variable amount of phenylarsonic acid which makes difficult quantitative polarographic measurements, because the electrodissolution potentials are varied and peak heights are masked. However, polarographic measurements are not altered through a wide range of phenylarsonic acid concentration if the solution is previously neutralized.