Efficient electron transfer in functional assemblies of pyridine-modified NQDs on SWNTs.
Nanocrystal quantum dot (NQD)/single-walled carbon nanotube (SWNT) hybrid nanomaterials were synthesized, assembled into field effect transistors (FETs) via dielectrophoresis (DEP), and characterized optically and electronically. The pyridine moiety functioned as a short, noncovalent linker between the NQDs and SWNTs and allowed more efficient carrier transfer through the assemblies without deleteriously altering electronic structures. Photoluminescence studies of the resulting assemblies support an efficient carrier transfer process in CdSe-py-SWNTs unlike that of CdSe/ZnS-py-SWNTs. The use of DEP as a means of controlling the assembly process allowed the creation of a SWNT array containing densely packed CdSe NQDs across a 2 mum gap between electrodes. Observations and characterization of the photocurrent, resistivity, gate dependence, and optical properties of these systems suggest efficient electron transfer from photoexcited NQDs to SWNTs.
Jeong
Sohee
S
Nanomechanical Systems Research Division, Korea Institute of Machinery and Materials (KIMM), Daejeon 305-343, Korea. sjeong@kimm.re.kr
Shim
Hyung Cheoul
HC
Kim
Soohyun
S
Han
Chang-Soo
CS
D019187:Cadmium Compounds / Q000737:chemistry; D004579:Electron Transport; D004586:Electrophoresis; D008163:Luminescent Measurements; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D013440:Sulfides / Q000737:chemistry; D014173:Transistors, Electronic; D017967:Zinc Compounds / Q000737:chemistry
D019187:Cadmium Compounds; D037742:Nanotubes, Carbon; D011725:Pyridines; D018036:Selenium Compounds; D013440:Sulfides; D017967:Zinc Compounds; C058667:cadmium selenide; C031238:zinc sulfide; C023666:pyridine