Highly Flexible Coaxial Nanohybrids Made from Porous TiO2 Nanotubes

Anatase TiO2, an n-type semiconductor, has gained considerable research interest over several decades due to its photocatalytic activity. Most recently, its properties for photoelectrical conversion in solar cells has been explored. Anodized TiO2 nanotube (NT) arrays have been developed and possess improved photocatalytic, sensing, photoelectrolystic, and photovoltaic properties. The present work describes using TiO2 as the building block to form ordered heterojunctions via simple electrodeposition with materials of potential interest, including conducting polymers (polypyrrole, poly(3-hexylthiophene)), inorganic semiconducting materials (CdS), and metals (Ni and Au, etc.). A key finding is that the synthesized TiO2 NT-nanowires(nanotubes) nanohybrids are highly flexible after being peeled off from mother substrates, which is in contrast to more fragile pure TiO2 NTs. These highly flexible coaxial nanohybrids are expected to have potent applications.