TY - JOUR
T1 - Thiol-capped germanium nanocrystals
T2 - Preparation and evidence for quantum size effects
AU - Muthuswamy, Elayaraja
AU - Zhao, Jing
AU - Tabatabaei, Katayoun
AU - Amador, Marlene M.
AU - Holmes, Michael A.
AU - Osterloh, Frank E.
AU - Kauzlarich, Susan M.
PY - 2014/3/25
Y1 - 2014/3/25
N2 - Applications of Ge nanocrystals (NCs) are limited by the stability and air reactivity of the Ge surface. In order to promote stability and increase the diversity of ligand functionalization of Ge NCs, the preparation of thiol-passivated Ge NCs via a ligand exchange process was investigated. Herein a successful replacement of oleylamine ligands on the surface of Ge NCs with dodecanethiol is reported. The successful ligand exchange was monitored by FTIR and NMR spectroscopy and it was found that dodecanethiol provided a better surface coverage, leading to stable Ge NC dispersions. Dodecanethiol capping also enabled band gap determination of the NCs by surface photovoltage (SPV) spectroscopy. The SPV measurements indicated an efficient charge separation in the ligand-exchanged Ge NCs. On the other hand, oleylamine-terminated Ge NCs of similar sizes exhibited a very small photovoltage, indicating a poorly passivated surface.
AB - Applications of Ge nanocrystals (NCs) are limited by the stability and air reactivity of the Ge surface. In order to promote stability and increase the diversity of ligand functionalization of Ge NCs, the preparation of thiol-passivated Ge NCs via a ligand exchange process was investigated. Herein a successful replacement of oleylamine ligands on the surface of Ge NCs with dodecanethiol is reported. The successful ligand exchange was monitored by FTIR and NMR spectroscopy and it was found that dodecanethiol provided a better surface coverage, leading to stable Ge NC dispersions. Dodecanethiol capping also enabled band gap determination of the NCs by surface photovoltage (SPV) spectroscopy. The SPV measurements indicated an efficient charge separation in the ligand-exchanged Ge NCs. On the other hand, oleylamine-terminated Ge NCs of similar sizes exhibited a very small photovoltage, indicating a poorly passivated surface.
UR - http://www.scopus.com/inward/record.url?scp=84896962673&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84896962673&partnerID=8YFLogxK
U2 - 10.1021/cm4042154
DO - 10.1021/cm4042154
M3 - Article
AN - SCOPUS:84896962673
VL - 26
SP - 2138
EP - 2146
JO - Chemistry of Materials
JF - Chemistry of Materials
SN - 0897-4756
IS - 6
ER -