Facile Controlled Synthesis and Spectroscopy of CdS 1− x Se x Alloy and (CdS) 1− x @(CdSe) x Core–Shell Nanotetrapods

Nanotetrapods of alloy CdS 1− x Se x and core–shell (CdS) 1− x @(CdSe) x are fabricated easily in water using ethylenediamine as a solvent‐coordinating molecular template, and then their optical properties are investigated using diverse static and time‐resolved spectroscopic methods. The arms of the alloy nanotetrapods have single‐crystalline structures of CdS 1− x Se x without showing staking faults, while the arms of the core–shell nanotetrapods display polycrystalline shell structures of CdSe. The optical properties of CdS 1− x Se x , where Se atoms are isolated in the CdS lattice, are very different from those of (CdS) 1− x @(CdSe) x , where banded CdSe passivates the CdS core. Compared with pure CdS nanotetrapods, the photoluminescence of CdS 0.9 Se 0.1 shifts to the red by 40 nm, whereas that of (CdS) 0.9 @(CdSe) 0.1 does so only by 5 nm. Although the mean luminescence lifetime of alloy CdS 1− x Se x is shorter than that of pure CdS, it is still much longer than that of core‐shell (CdS) 1− x @(CdSe) x .