中国物理B ›› 2001, Vol. 10 ›› Issue (13): 70-75.

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

SELF-ASSEMBLY AND POLARIZABILITY OF CAPPED CdS NANOCRYSTALS ON SILICON SURFACES

巴龙, 张宇, 陆祖宏   

  1. Laboratory of Molecular and Biomolecular Electronics, Southeast University, Nanjing 210096, China
  • 收稿日期:2001-04-20 出版日期:2005-07-07 发布日期:2005-07-07
  • 基金资助:
    Project supported by the "Nanoelectronics" Key Project (69890200) of National Natural Science Foundation of China.

SELF-ASSEMBLY AND POLARIZABILITY OF CAPPED CdS NANOCRYSTALS ON SILICON SURFACES

Ba Long (巴龙), Zhang Yu (张宇), Lu Zu-hong (陆祖宏)   

  1. Laboratory of Molecular and Biomolecular Electronics, Southeast University, Nanjing 210096, China
  • Received:2001-04-20 Online:2005-07-07 Published:2005-07-07
  • Supported by:
    Project supported by the "Nanoelectronics" Key Project (69890200) of National Natural Science Foundation of China.

摘要: The zinc-blende CdS nanocrystals with particle size less than 10nm were prepared in solution with a molecular surfactant. The particle surface was modified with capping molecules, bis(2-ethylhexyl) sulfosuccinate disodium salt (AOT) or hexametaphosphate (HMP). The colloid solution was deposited on silicon wafer and the assembly of these nanocrystals was studied by atomic force microscopy. It was found that the CdS/AOT formed a monolayer by simply dropping the colloid solution on silicon surface, while CdS/HMP exhibited 3D structure with prefered orientation in the similar deposition process. A dynamic electric force microscopy was performed and the polarizability was measured from the resonance of cantilever under applied alternating voltage between tip and substrate. The dielectric constant of CdS nanocrystal was estimated by comparing the different electric capacitance of Au and CdS nanocrystals.

Abstract: The zinc-blende CdS nanocrystals with particle size less than 10nm were prepared in solution with a molecular surfactant. The particle surface was modified with capping molecules, bis(2-ethylhexyl) sulfosuccinate disodium salt (AOT) or hexametaphosphate (HMP). The colloid solution was deposited on silicon wafer and the assembly of these nanocrystals was studied by atomic force microscopy. It was found that the CdS/AOT formed a monolayer by simply dropping the colloid solution on silicon surface, while CdS/HMP exhibited 3D structure with prefered orientation in the similar deposition process. A dynamic electric force microscopy was performed and the polarizability was measured from the resonance of cantilever under applied alternating voltage between tip and substrate. The dielectric constant of CdS nanocrystal was estimated by comparing the different electric capacitance of Au and CdS nanocrystals.

Key words: nanoparticle, self-assembly, scanning probe microscopy

中图分类号: 

  • 7320