Germanium nanowire synthesis from fluorothiolate-capped gold nanoparticles in supercritical carbon dioxide
Koleśnik-Gray, Maria M.
Holmes, Justin D.
American Chemical Society (ACS)
Ge nanowires seeded from Au nanoparticles capped with fluorothiolate ligands were synthesized in supercritical carbon dioxide (sc-CO2) by the thermal decomposition of diphenylgermane (DPG) at a temperature of 380 °C and a pressure of 25.7 MPa. Both perfluorinated and semifluorinated capped Au nanoparticles acted as effective catalysts for growing Ge nanowires, with mean diameters of 11 nm (σ = 2.8) and 14 nm (σ = 3.5), respectively. The mean diameter of the Ge nanowires grown from the fluorous-capped Au nanoparticles were considerably smaller than those synthesized from dodecanethiol-capped nanoparticles in sc-toluene, under the same reaction conditions, i.e., 28 nm and σ = 10.3. Differences in the ligand conformations on the surface of the Au nanoparticles and phase separation of the fluorocarbon/CO2 and hydrocarbon/toluene systems gave rise to greater steric stabilization of the fluorous-capped Au nanoparticles in CO2, resulting in small diameter nanowires with a relatively narrow size distribution. Electrical analysis of the nanowires showed them to be p-type (hole) semiconductors.
Gold , Carbon dioxide , Electric wire , Germanium , Ligands , Nanoparticles , Nanowires , Phase separation , Pyrolysis , Supercritical fluid extraction , Synthesis (chemical) , Toluene , Germanium nanowires
Collins, G., Koleśnik, M., Krstić, V. and Holmes, J. D. (2010) 'Germanium Nanowire Synthesis from Fluorothiolate-Capped Gold Nanoparticles in Supercritical Carbon Dioxide', Chemistry of Materials, 22(18), pp. 5235-5243. doi: 10.1021/cm1012137
© 2010 American Chemical Society. This document is the Accepted Manuscript version of a Published Work that appeared in final form in Chemistry of Materials, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/cm1012137