Synthesis, characterization and photoluminescence of CdS hyperbranched nanocrystals by a simple solution chemistry method

We report the synthesis of CdS hyperbranched nanocrystals using a simple hot coordination solvents method. Transmission electron microscopy studies showed that the length of the arms and the angle of branching could be controlled by varying organic surfactants in terms of amount and type. It was found that long chain carboxylic acids favored the synthesis of CdS hyperbranched nanocrystals. Although their absorption spectra of CdS hyperbranched nanocrystals did not display sharp features, the photoluminescence spectra showed two emission peaks, i.e., the corresponding luminescence peak around 486 nm originates from the band edge and the broad band emission from 560 nm extended to the region of near infrared arises from trap-related recombination of as-prepared CdS hyperbranched nanocrystals.