CdSe, ZnO 나노물질 광전특성 연구

Abstract

Attachment of CdSe quantum dot (QDs) and single-walled carbon nanotubes (SWNTs) has been performed. We have synthesized CdSe-pyrene-SWNTs hybrid via chemical bath deposition (CBD). CdSe QDs were synthesized by a heating method in which the particle size was controlled by changing reaction time. To attach the CdSe QDs to SWNTs, CdSe QDs were made to be water soluble by coating them with a monolayer of mercaptopropionic acid, a very short hydrophilic thiol. The ultraviolet/visible (UV/Vis), infrared (IR) spectra were measured to prove the CdSe-pyrene-SWNTs hybrid. The I-V characteristics and photocurrent of CdSe-pyrene-SWNTs hybrid were measured at room temperature. We can clearly see that a charge transfer process exists in the system. Zinc oxide (ZnO) nanorods have shown very unique properties for applications such as field emission (FE), light emitting diode (LED), transparent film of solar cell. In general, as-synthesized ZnO nanorods have n-type semiconducting properties. In our experiment, chemical bath deposition (CBD) is used synthesis of ZnO nanorods, and precursor ZnO layer is produced by magnetron sputtering on a p-type porous silicon (p-PS) for a p-n junction. Highly oriented nanorod arrays of ZnO were grown on the surface of the precursor ZnO layer by solution growth process using zinc nitrate and hexamethylenetetramine in equimolar aqueous solution. X-ray diffraction (XRD) analysis shows that the ZnO nanorods deposited on p-PS surface are non-crystalline because of the roughness of the PS surface. The photoluminescence (PL) and electroluminescence (EL) spectra from the ZnO nanorods on p-PS were obtained, which consists of blue and green emissions from ZnO nanorods and red emission from p-PS. The emission properties of ZnO nanorods on p-PS were examined due to their nanorod geometry and high aspect ratio.