Accession Number : ADA288381

Title :   Chemistry Involving the Separation, Isolation, and Immobilization of Ill-V Compound Semiconductor Nanocrystals and Quantum Dots.

Descriptive Note : Annual technical rept. 1 Oct 93-20 Sep 94,

Corporate Author : DUKE UNIV DURHAM NC DEPT OF CHEMISTRY

Personal Author(s) : Wells, Richard L. ; Coury, Louis A.

PDF Url : ADA288381

Report Date : 14 SEP 1994

Pagination or Media Count : 11

Abstract : The facile thermolysis of Cl2GaP(SiMe3)22 to eliminate Me3 SiX and yield nanocrystalline GaP has been studied via thermal gravimetric analysis (TGA) and it has been found that the Me3SiCl is eliminated in a step-wise manner. Also, the new ternary single-source precursor Ga2(As,P)C13n has been synthesized and thermolyzed to yield the ternary III-V GaAsxPy. In addition, nanocrystalline GaAs and GaP, prepared by the Kher/Wells low temperature solution phase method, have been studied by transmission electron microscopy (TEM) and, in the TEM's of both, the lattice fringes of nanocrystalline material are clearly evident. Using a host of analytical techniques, it has been shown that the GaAs has crystalline regions of 12 + or - 2 nm. In addition, efforts in immobilization of particles have involved all binary permutations of In and Ga phosphides and arsenides. The materials have been cast onto electrode surfaces from volatile solvents to give uniform deposits. Dispersions can also be created in the presence of monomers which are subseqently electropolymerized to prepare composite films. In an STM plot of InAs immobilized in a poly(pyrrole) film, the nanocrystals appear as yellow dots embedded in the brown film, indicating that they extend above the film, and/or have a higher conductivity than the polymer.

Descriptors :   *ISOLATION, *CRYSTALS, *SEMICONDUCTORS, *SEPARATION, *GROUP III COMPOUNDS, *GROUP IV COMPOUNDS, *GROUP V COMPOUNDS, CONDUCTIVITY, POLYMERS, COMPOSITE MATERIALS, GALLIUM ARSENIDES, FILMS, ELECTRON MICROSCOPY, TRANSMITTANCE, SURFACES, CHEMISTRY, DEPOSITS, PARTICLES, THERMAL ANALYSIS, ELECTRODES, ARSENIDES, GALLIUM, GRAVIMETRIC ANALYSIS, MONOMERS, PHOSPHIDES, PYRROLES, RESTRAINT, SOLVENTS, VOLATILITY, QUANTUM ELECTRONICS.

Subject Categories : Physical Chemistry
      Inorganic Chemistry
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE