Polyaniline deposited on As2O3 surface resulted in a new material, which wa
s characterized by infrared spectoscopy, thermogravimetry, differential sca
nning calorimetry, scanning electron microscopy, X-ray diffraction, and cyc
lic voltammetry, The mass percentage of polymer deposited on oxide surface
is approximately 13%, The scanning electron microscopy images as well as th
e X-ray diffraction patterns provided conclusive evidence that the oxide su
rface is coated by the polymer. The cyclic voltammograms of the polyaniline
adsorbed on As2O3 surface showed that the adsorbate exerts remarkable effe
cts on redox processes on this oxide. The pure oxide exhibited two oxidatio
n/rcduction peaks at 0.25/-0.06 and 0.47/-0.25 V attributed tentatively to
the processes As2O3(s) + 6H(+) + 6e(-) = 2As(s) + 3H(2)O and As(s) + 3H(+)
+ 3e(-) = AsH3(g), respectively. The polyaniline-coated sample exhibited a
better-defined voltammogram in which the first oxidation peak of the oxide
had its intensity increased about four times. (C) 2000 Academic Press.