Synthesis and characterization of CdSe/CdTe heterostructured nano-tetrapods

Tetrapod-shaped heterostructured nanocrystals are promising materials in photoelectric devices due to their special morphology and structure. In this paper, CdSe/CdTe heterostructured nano-tetrapods with type II band alignment were synthesized by a simple chemical method in solution. High-resolution transmission electron microscopy (HRTEM) images show that CdSe/CdTe heterostructures are composed by CdSe tetrapod with CdTe nanorods epitaxially grown on the four arms. No core–shell heterostructures were observed. UV–visible absorption spectroscopy (UV–vis) shows that the absorption peak of CdSe/CdTe heterostructure tetrapod nanocrystals is red-shift comparing with that of CdSe tetrapod-shaped nanocrystals. It is also weaker and broader than that of nano-tetrapods. The room-temperature photoluminescence (PL) intensity of heterostructures is much weaker than that of CdSe nano-tetrapods. It is believed that it is due to the spatial separation of electrons and holes in heterostructures.