Layer-by-layer self-assembly replication technique: application to photoelectrode of dye-sensitized solar cell

A new replication method of depositing the crystalline TiO2 thin film on the nanoporous multilayer film of weak-polyelectrolytes, that is, the combination of the chemical solution deposition and layer-by-layer self-assembly method is proposed. Scanning electron microscopic observation revealed that the nanoporous and extremely high surface area TiO2 thin film, well imprinted with the surface structure and the inside nano-structure of layer-by-layer self-assembled thin film using as the replica, was successfully fabricated. By using the nanoporous TiO2 thin film with high surface area as the photoelectrode for dye-sensitized solar cell, the improvement of the photocurrent-voltage characteristic was achieved, resulting in an energy conversion efficiency of η=0.70%