Hetero-seed meditated method to synthesize ZnO/TiO2 multipod nanostructures with ultra-high yield for dye-sensitized solar cells

Abstract

ZnO multipod nanostructures are widely used for their unique structures. However, the large-scale synthesis of these materials is a challenge for the practical applications. In this paper, we used a hetero-seed mediated hydrothermal method to synthesize ZnO/TiO2 multipod nanostructures with ultra-high yield. The TiO2 nanoparticles were used as the seeds and nucleated centers for the following ZnO nanorods growth, in which these ZnO nanorods scattered from the TiO2 nanoparticles to form ZnO/TiO2 multipod nanostructures. The diameter and length of these ZnO nanorod branches were controlled by the amount of TiO2 nanoparticles. The yield of pure ZnO/TiO2 multipod nanostructures can reach 20.0 g/L within 20 min heating time. When used as the anodes of dye-sensitized solar cells (DSSCs), a photoelectric conversion efficiency of 3.1% has been achieved when using these ZnO/TiO2 multipod nanostructures as the anodes of DSSC. This is due to the one-dimensional (1D) nanostructures are promising by fastening electron transport to reduce the charge recombination. As a result, this provides a simple method to synthesize ZnO/TiO2 multipod nanocomposites with high yield and low cost, which can be used as the photoanodes for high efficient DSSCs and photocatalysts.