The epitaxial growth of germanium on silicon leads to the self-assembly of SiGe nanocrystals by a process that allows the size, composition and position of the nanocrystals to be controlled. This level of control, combined with an inherent compatibility with silicon technology, could prove useful in nanoelectronic applications. Here, we report the confinement of holes in quantum-dot devices mad...

Bismuth sulfide (Bi2S3) is a narrow-bandgap semiconductor that is an interesting candidate for fluorescent biomarkers, thermoelectrics, photocatalysts, and photovoltaics. This study reports the synthesis and characterization of novel Bi2S3 quantum dots (QDs) functionalized using chitosan (CHI) as the capping ligands via aqueous "green" route at room temperature and ambient pressure. Transmissio...

This review focuses on recent progress in the study of doped semiconductor nanocrystals prepared by direct solution chemical routes. The emphasis is on materials that can be prepared and handled as high-quality colloidal nanocrystalline suspensions, allowing them to be easily processed by a variety of conventional methods and incorporated into glasses, polymers, or hetero-architectures, appende...

nanoribbons, [ 10 ] and most recently nanoplatelets (NPLs) [ 11 ] have been successfully synthesized. In these solution-processed quantum structures, an additional epitaxial growth of semiconductor shell around the starting semiconductor core leads to various architectures of nanocrystal heterostructures. By doing so, physical properties can be elegantly modifi ed with precisely controlling dis...

High-quality nanocrystals formed in organic solvents can be completely solubilized in water using amphiphilic copolymers containing poly(ethylene glycol) or PEG. These copolymers are generated using a maleic anhydride coupling scheme that permits the coupling of a wide variety of PEG polymers, both unfunctionalized and functionalized, to hydrophobic tails. Thermogravimetric analysis, size exclu...

We report on three-photon excited band edge and trap emission of CdS semiconductor nanocrystals. While the band edge emission intensity clearly shows a cubic dependence on excitation intensity, demonstrating three-photon absorption process, the trap emission does not exhibit such a cubic dependence. A simple theoretical model based on the assumption that there exist a limited number of trap sta...

Phase transfer techniques possess remarkable advantages for the synthesis of inorganic nanomaterials. In contrast to the abundant reports on the preparation of noble metal nanoparticles using phase transfer, the number of semiconductor nanocrystals syntheses based on phase transfer techniques is still limited. Herein, we report a systematic study of the phase transfer-based synthesis of HgS nan...

An all-organic memory device based on a copper phthalocyanine (CuPc) thin-film transistor (TFT) using gold nanocrystals embedded in a polyimide gate dielectric is demonstrated. Both the gate dielectric and the active semiconductor layer are organic materials. Discrete gold nanocrystals are adopted as the charge storage medium. Under proper gate bias, gold nanocrystals are charged and discharged...

Local fluorescence probes based on CdSe semiconductor nanocrystals were prepared and tested by recording scanning near-field optical microscopy (SNOM) images of calibration samples and fluorescence resonance energy transfer SNOM (FRET SNOM) images of acceptor dye molecules inhomogeneously deposited onto a glass substrate. Thousands of nanocrystals contribute to the signal when this probe is use...

Cation exchange is a powerful tool for the synthesis of nanostructures such as core-shell nanocrystals, however, the underlying mechanism is poorly understood. Interactions of cations with ligands and solvent molecules are systematically ignored in simulations. Here, we introduce the concept of pseudoligands to incorporate cation-ligand-solvent interactions in molecular dynamics. This leads to ...