COMPOSITIONAL ANALYSIS OF ORGANIC-INORGANIC SEMICONDUCTOR COMPOSITES

Compositional analysis of composite powders containing organic and ino rganic semiconductor components was performed by thermogravimetric ana lysis (TGA). Two model composites, consisting of poly(aniline) (PAN) a s the matrix and either WO3 or TiO2 particles dispersed therein, were used to illustrate the analytical methodology, In both cases, the oxid e semiconductor component asymptotically approached a saturation level in the composite, as the initial medium content was varied from 0 to 120 mg (per 15 ml), Chemical polymerization was used to prepare the PA N-WO3 and PAN-TiO2 composites, Cyclic voltammetric data mainly reflect the PAN component in the composite although voltammograms acquired un der chopped illumination of the working electrode reveal the photoacti vity of the oxide component. The TGA data were linearly correlated wit h compositional assays as performed by laser Raman spectroscopy for th e PAN-WO3 case, The relative analytical merits of the two techniques f or the analysis of composite samples are discussed.