Accession Number : ADA289042

Title :   Self Assembly of n-Alkanethiolate Monolayers on Silver Nano-Structures: Protective Encapsulation.

Descriptive Note : Interim rept. May 93-Jun 94,

Corporate Author : CALIFORNIA UNIV IRVINE DEPT OF CHEMISTRY

Personal Author(s) : Li, Wenjie ; Virtanen, Jorma A. ; Penner, Reginald M.

PDF Url : ADA289042

Report Date : 18 DEC 1994

Pagination or Media Count : 24

Abstract : Silver nanostructures having dimensions of 200-1000A in diameter and 2O-5OA in height were synthesized on graphite surfaces using the scanning tunneling microscope (STM). Although these nanostructures were stable while immersed in aqueous solutions containing small (0.5 mM) concentrations of Ag+, upon transfer into pure water, dissolution of the nanostructure occurred within 30 minutes, irrespective of the applied imaging bias up to +200 mV. Anodic dissolution was inhibited following the formation of an n-alkane thiolate self-assembled monolayer (SAM) on the silver surface, demonstrating that molecular self- assembly provides a method for the protective, and chemically selective, encapsulation of reactive nanometer-scale structures on solid surfaces. Self-assembly was not observed following the exposure to long-chain n-alkyl amines or carboxylic acids.

Descriptors :   *ALKANES, *PROTECTION, *ENCAPSULATION, *SILVER, SCANNING ELECTRON MICROSCOPES, BIOLOGY, SOLUTIONS(MIXTURES), SYNTHESIS, LAYERS, WATER, TUNNELING(ELECTRONICS), GRAPHITE, SURFACES, AMINES, PURITY, IMAGES, ASSEMBLY, BIAS, SOLID BODIES, CARBOXYLIC ACIDS, ALKYL RADICALS.

Subject Categories : Organic Chemistry
      Inorganic Chemistry
      Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE