Hybrid electrochemical/chemical synthesis of quantum dots.
The "electrochemical/chemical method" (or "E/C method") is a new wet chemical method for synthesizing semiconductor quantum dots on graphite surfaces. The E/C synthesis of quantum dots composed of the generic semiconducting salt, MX, typically involves three steps: (1) electrochemical deposition of nanoparticles of the metal, M degrees, from a solution of metal ions, M(n)(+); (2) electrochemical oxidation of these metal particles to MO(n)()(/2), and; (3) displacement of the oxygen from MO(n)()(/2) using HX (for example) to yield nanoparticles of MX. This conversion from metal to metal oxide to metal salt occurs on a particle-by-particle basis; that is, each metal nanoparticle is converted into a semiconductor nanoparticle. E/C-synthesized beta-CuI and CdS quantum dots possess many of the attributes of quantum dots synthesized using molecular beam epitaxy, including epitaxial orientation on the graphite surface, a narrow size dispersion, and strong, particle size-tunable photoluminescence. However, the E/C method is faster, cheaper, and applicable to a greater number of materials.
Penner
R M
RM
Institute for Surface and Interface Science, Department of Chemistry, University of California, Irvine, California 92679-2025, USA. rmpenner@uci.edu
D004563:Electrochemistry; D008670:Metals; D008832:Microchemistry; D018625:Microscopy, Atomic Force; D010084:Oxidation-Reduction; D010316:Particle Size; D012666:Semiconductors
D008670:Metals