Preparation of polyaniline/TiO₂ composite nanotubes for photodegradation of AZO dyes

Abstract

Polyaniline (PANI) composite nanotubes (90–130 nm in diameter) containing titanium dioxide (TiO₂) nanoparticles (about 10 nm in diameter) were synthesized through a self-assembly process in the presence of â-naphthalenesulfonic acid (â-NSA) as the dopant. It was found that PANI-TiO₂ composites and PANI nanotubes both behaved with significant photocatalytic activities towards AZO dyes, during 2 h photocatalytic processes under natural light, the degradation ratio was 94.2% and 97.2% respectively (methyl orange and orange II). The morphology of such products was characterized by SEM. The specific surface area of such composite nanotubes was 14.7 m²/g compared to normal polyaniline which was 0.27 m²/g. IR and X-ray diffraction characterizations showed that the chemical chain of the composite nanotubes was identical to that of the doped PANI. It may provide a new way for photodegradation of organic contaminants by using conjugated polymer with dimensional structure.

Keywords

polyaniline / TiO₂ / nanotube / photocatalysis

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