We describe the synthesis of water-soluble semiconductor nanoparticles and discuss and characterize their properties. Hydrophobic CdSe/ZnS core/shell nanocrystals with a core size between 2 and 5 nm are embedded in a siloxane shell and functionalized with thiol and/or amine groups. Structural characterization by AFM indicates that the siloxane shell is 1-5 nm thick, yielding final particle size...

ZnxCd1-xSe/C core/shell nanocrystals with 31-39 nm diameter semiconductor cores and 11-25 nm-thick carbon shells were synthesized from solid state precursors in large scale amounts. Transmission electron microscopy (TEM) showed striations in the nanocrystals that are indicative of a composition modulation, and reveal a chemical phase separation and possible spinodal decomposition within the nan...

Cesium lead halide nanocrystals, CsPbX3 (X = Cl, Br, I), exhibit photoluminescence quantum efficiencies approaching 100% without the core-shell structures usually used in conventional semiconductor nanocrystals. These high photoluminescence efficiencies make these crystals ideal candidates for light-emitting diodes (LEDs). However, because of the large surface area to volume ratio, halogen exch...

Optical, electronic and structural properties of nanocrystals fundamentally derive from crystal phase. This is especially important for polymorphic II-VI, III-V and I-III-VI2 semiconductor materials such as cadmium selenide, which exist as two stable phases, cubic and hexagonal, each with distinct properties. However, standard crystallographic characterization through diffraction yields ambiguo...

In this paper, we synthesized a novel type II cuprous sulfide (Cu(2)S)-indium sulfide (In(2)S(3)) heterostructure nanocrystals with matchstick-like morphology in pure dodecanethiol. The photovoltaic properties of the heterostructure nanocrystals were investigated based on the blends of the nanocrystals and poly(2-methoxy-5-(2'-ethylhexoxy)-p-phenylenevinylene) (MEH-PPV). In comparison with the ...

We use aerosol techniques to investigate the cohesive and granular properties of solids composed of colloidal semiconductor nanocrystals (quantum dot solids). We form spherical agglomerates of nanocrystals with a nebulizer and direct them toward a carbon substrate at low (~0.01 m/s) or high (~100 m/s) velocities. We then study the morphology of the deposit (i.e., the "splat") after impact. By v...

Magnetic nanocrystals have been investigated extensively in the past several years for several potential applications, such as information technology, MRI contrast agents, and for drug conjugation and delivery. A specific property of interest in biomedicine is magnetic hyperthermia-an increase in temperature resulting from the thermal energy released by magnetic nanocrystals in an external alte...

K5NdLi2F10 nanocrystals were synthesized by a novel synthetic route in the liquid phase, which could improve the morphology and reduce the size effectively, for the first time. The luminescence intensities of the K5NdLi2F10 nanocrystals and their dispersion in polyethylene glycol 400 (PEG-400) approximate to that of neodymium doped phosphate glass (3 mol%), while the lifetimes of the nanocrysta...

Diamond cubic Sn-rich nanocrystals were fabricated with radii less than 20 nm by post-growth annealing at T = 750 ◦C of SnxGe1−x alloys grown on Ge(001) by molecular beam epitaxy. The crystal phase of the Sn-rich nanocrystals was determined to be diamond cubic from Fourier transform analysis of high-resolution transmission electron microscopy images. Optical transmittance of these SnxGe1−x/Ge (...

We present a review on the emerging materials for novel plasmonic colloidal nanocrystals. We start by explaining the basic processes involved in surface plasmon resonances in nanoparticles and then discuss the classes of nanocrystals that to date are particularly promising for tunable plasmonics: non-stoichiometric copper chalcogenides, extrinsically doped metal oxides, oxygen-deficient metal o...