Fabrication of polymer/TiO₂-nanotube-based hybrid structures using a solvent-vapor-assisted coating method

The incomplete infiltration and ununiform coating of polymer material in inorganic nanostructures have hindered the applications of hybrid nanostructure. In this work, a novel solvent-vapor-assisted coating (SVAC) method is proposed for uniform coating of polymers in inorganic nanostructure. It is demonstrated that the thickness of the polymer layer in TiO₂ nanotubes can be simply controlled using processing temperatures. At moderate temperatures, the polymer nanotubes which showed unique chain ordering formed in ordered TiO₂ nanotubes. Hybrid solar cells, made by filling the tube-in-tube structure with hole transporting material, produced drastically improved short circuit current and serial resisitance. The results imply that the proposed method has potential to improve performance of devices with hybrid nanostructures by controlling the morphology of polymer layer.