Three synthetic routes to single-crystalline PbS nanowires with controlled growth direction and their electrical transport properties.
Single-crystalline rock-salt PbS nanowires (NWs) were synthesized using three different routes; the solvothermal, chemical vapor transport, and gas-phase substitution reaction of pregrown CdS NWs. They were uniformly grown with the [100] or [110], [112] direction in a controlled manner. In the solvothermal growth, the oriented attachment of the octylamine (OA) ligands enables the NWs to be produced with a controlled morphology and growth direction. As the concentration of OA increases, the growth direction evolves from the [100] to the higher surface-energy [110] and [112] directions under the more thermodynamically controlled growth conditions. In the synthesis involving chemical vapor transport and the substitution reaction, the use of a lower growth temperature causes the higher surface-energy growth direction to change from [100] to [110]. The high-resolution X-ray diffraction pattern and X-ray photoelectron spectroscopy results revealed that a thinner oxide-layer was produced on the surface of the PbS NWs by the substitution reaction. We fabricated field effect transistors using single PbS NW, which showed intrinsic p-type semiconductor characteristics for all three routes. For the PbS NW with a thinner oxide layer, the carrier mobility was measured to be as high as 10 cm(2) V(-1) s(-1).
Jang
So Young
SY
Department of Chemistry, Korea University, Jochiwon 339-700, Korea.
Song
Yun Mi
YM
Kim
Han Sung
HS
Cho
Yong Jae
YJ
Seo
Young Suk
YS
Jung
Gyeong Bok
GB
Lee
Chi-Woo
CW
Park
Jeunghee
J
Jung
Minkyung
M
Kim
Jinhee
J
Kim
Bongsoo
B
Kim
Jin-Gyu
JG
Kim
Youn-Joong
YJ