Prototype of a scalable core-shell Cu 2O/TiO 2 solar cell

Titanium oxide (TiO₂) nanotube membranes are synthesized via a two-step anodization method. The conductivity at the crystallized barrier layer is enhanced by NH₄Cl treatment. This facilitates electrodeposition of Cu₂O into TiO₂ nanotubes, creating Cu₂O/TiO₂p-n heterojunctions in the radial direction. The photovoltaic performances benefit from the increased junction interface as well as the efficient pathway for separated charges to transport through the one-dimensional channel. Such heterojunction system serves as a promising candidate for solid-state solar cell due to its scalability, abundancy, low cost and environmental friendly nature. In addition, this versatile process can be conducted on various materials with the potential applications in photovoltaics, supercapacitor, battery, catalyst, etc.