Effect of gold adsorption on the conductive properties of cyclo-octasulfur microcrystals.
The formation of gold crystallites on the surface of S8 promotes diffusion of electrons and determines the conductive properties of the shell-core nanosystems. Conducting probe atomic microscopy and four-probe resistance measurements confirmed that Au/S8 shell-core systems exhibit electrical conductivity on the micro- as well as on the nanoscale in contrast to non-covered S8 crystals, which are insulating. The conductivity of Au/S8 systems on the microscale was measured to be 10+/-1 S cm(-1). In XPS measurements, a single peak at 163.6 eV was observed for bulk S8 whereas an additional peak corresponding to a binding energy of 161.4 eV appeared for S8 adsorbed on a Au substrate. This is interpreted to mean that a chemical reaction has taken place. A process which results in adsorption of uniform gold nanolayers on needle shaped or fibrous S8 crystallites is under investigation.
Vaganova
E
E
Department of Inorganic and Analytical Chemistry, The Hebrew University of Jerusalem, 91904, Jerusalem, Israel.
Leitus
G
G
Wachtel
E
E
Popov
I
I
Shimoni
N
N
Olea
D
D
Gomez-Herrero
J
J
Yitzchaik
S
S