Combinations of N, P-type semiconductors and conductor (γ-Fe2O3, polypyrrole and silver) as different nanostructural nanocomposites for adsorptive and photocatalytic application

Several hetero-junction nanocomposites consisting of N- and P-type semiconductors and conductor (gamma-Fe2O3, polypyrrole and silver) were prepared here by radical polymerization and redox method for adsorptive and photocatalytic applications. The obtained materials were characterized by means of X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Infrared spectroscopy, and ultraviolet-visible absorption measurement. The results indicated that the average size of gamma-Fe2O3 nanoparticles from all the samples is approximately 26.5 nm, the Ag nano-crystal with a average size of 19.2 nm attached on the interface of gamma-Fe2O3 and the polypyrrole or polypyrrole surface and has good dispersivity. The adsorptive and photocatalytic activities of the above composites were studied before and after 2 h photodegradation of Methyl Orange and Orange II. Considering the adsorptive and photocatalytic performances as a whole, Fe2O3/polypyrrole composites based on the P-N-type hetero-junction exhibited the highest removal ability towards azo dyes compared with all the other as-prepared samples, and the total removal ratios towards Methyl Orange and Orange II were 84.3 and 92.6 %, respectively.