@article{Yang2015, 
author = {Yu Yang and Jiongzhao Li and Long Lin and Xiaogang Peng},
title = {An efficient and surface-benign purification scheme for colloidal nanocrystals based on quantitative assessment},
year = {2015},
journal = {Nano Research},
volume = {8},
number = {10},
pages = {3353-3364},
keywords = {colloidal nanocrystals, purification, metal carboxylates, ligands, chloroform-acetonitrile},
url = {https://www.sciopen.com/article/10.1007/s12274-015-0835-6},
doi = {10.1007/s12274-015-0835-6},
abstract = {General application of "greener methods" to the synthesis of monodisperse colloidal nanocrystals introduces impurities, including metal carboxylate precursors, non-volatile solvents, free ligands, and non-nanocrystalline side products. These impurities seriously diminish the solution processability and potential applications of colloidal nanocrystals. A protocol was established for evaluating purification schemes. The results revealed that commonly applied purification schemes and their variants do not exhibit a high level of performance and may degrade the ligand surface coverage. A new scheme involving chloroform–acetonitrile precipitation quantitatively removed all impurities from colloidal solutions of CdSe and CdS nanocrystals coated with a variety of carboxylate ligands. The new scheme was benign to the surface structure of nanocrystal-ligands complexes and resulted in each nanocrystal bearing a close-packed monolayer of carboxylate ligands.}
}