Elucidation and advancement of the CdS nanocrystal formation process

by Li, Zheng; Xie, Renguo; Grisham, Susan Y.; Peng, Xiaogang

The synthesis of CdS nanocrystals in non-coordinating solvent (1-octadecene, ODE) was chosen as the model system to study its relevant formation process. By varying the synthesis protocols, the reaction evolutions were monitored ex-situ via UV-Vis and FT-IR, and the rate-detg. step for the formation of CdS nanocrystals was identified. Addnl., with the aid of NMR and GC-MS, the underlying mol. mechanism was further elucidated. Preliminary quant. anal. was in accordance with the reaction mechanism. Furthermore, the reaction's crit. temp. was detd., and the synthetic protocol was further enhanced based on the results from studying the CdS nanocrystals formation process. The synthesis temp. could also be lowered via the introduction of an activator. By interpreting the exptl. results carefully and using the relevant knowledge to optimize the synthesis of CdS nanocrystals, it is clear that the significance of mechanism studies should not be undermined.