Nanostructured TiO₂/Polypyrrole for Visible Light Photocatalysis

Stable TiO2/polypyrrole nanocomposites have been synthesized by a simple one-step hydrothermal method. The nanocomposites are capable of efficient visible-light photocatalysis driven by their morphology that utilizes a high concentration of 4.5 nm TiO2 nanoparticles electronically coupled to 200–300 nm polypyrrole granules. The polypyrrole acts as visible-light photosensitizer, and the photoactivity of nanocomposite arises from the electron transfer from excited polypyrrole to TiO2 nanoparticles and further across nanocomposite interface. The visible-light photocatalysis is demonstrated by methylene blue degradation and by the production of H2 from water with efficiency of 1 mmol H2 gcatalyst–1 h–1 wt %(Pt)−1.