Size dependent photoluminescence properties of CdZnS nanostructures

Photoluminescence response of cadmium zinc sulfide (CdZnS) nanostructures has been studied through low-temperature and time-resolved photoluminescence measurements. The as synthesize nanostructures are single crystalline having growth along [102] direction. The CdZnS nanostructures exhibited near band edge and deep level emission bands at 2.485 eV and 2.09 eV, displaying bi-exponential excitonic decay with an average lifetime of 2.56 ns and 4.11 ns, respectively. Furthermore, single CdZnS nanostructures have been investigated for their size dependent photoluminescence properties. For isolated nanostructures, emission band systematically shifted towards the higher-energy, and defect-related low energy emission peak disappeared with a decrease in nanostructure width. Results revealed that emission originated from the radiative recombination process of the donor and acceptor bound excitons. Detrimental effect of low temperature Photoluminescence measurements have been observed in individual nanostructures. (C) 2016 Elsevier B.V. All rights reserved.