Fabrication of hierarchical ZnO/TiO2 core-shell nanostructures for advanced photovoltaic devices

The advancement of nanomaterials and nanotechnology has provided huge potential to improve solar cell performance with an expectation of reducing the cost and improving the cell efficiency. Significant research has been done on nanorod based solar cells in recent years. In order to increase surface area and improve the light trapping effect for cell efficiency enhancement, 3-D hierarchical ZnO nanostructures and ZnO/TiO₂ core-shell structures including nanorods, nanosheets, and nanoshrubs have been developed by using a solution based, two-step deposition process. The extremely large surface area is expected to improve dye loading and charge injection along with the improved light trapping, all of which helps to increase the energy conversion efficiency in dye-sensitized solar cells. These solar cells were fabricated using the core-shell nanostructures, which showcases the potential of the unique nanomaterials in advanced photovoltaics.