Heterogeneous flammulina velutipes-like CdTe/TiO2 nanorod array: A promising composite nanostructure for solar cell application

Core–shell heterogeneous CdTe/TiO2 nanorod arrays have been prepared by a two-step synthesis route through combined hydrothermal growth and magnetron sputtering. The composition and microstructure of the arrays were investigated by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM), which show that CdTe nanograins coated on the surface of the single-crystalline TiO2 nanorod arrays to form a type-II heterostructure. Compared with TiO2 nanorod arrays, the spectrum absorption region of CdTe/TiO2 core–shell nanostructure is broadened from ultraviolet light to visible light. The photoelectrodes of CdTe/TiO2 nanorod arrays show better photoelectric properties than those of bare TiO2 nanorod arrays. The output power of CdTe/TiO2 nanorod arrays is 25 times higher than that of a bare TiO2 nanorod array. These results indicate that the photoelectrode of CdTe/TiO2 nanorod array has a promising application in solar cell.

► Core–shell CdTe/TiO2 nanorod arrays have been prepared via hydrothermal growth and magnetron sputtering method.
► CdTe nanograins covered on the surface of the TiO2 nanorod arrays constructing a flammulina velutipe like type-II heterostructure.
► The spectrum absorption region and the open circuit photocurrent are greatly increased.