Initially poorly conducting PbSe nanocrystal solids (quantum dot arrays or superlattices) can be chemically "activated" to fabricate n- and p-channel field effect transistors with electron and hole mobilities of 0.9 and 0.2 square centimeters per volt-second, respectively; with current modulations of about 10(3) to 10(4); and with current density approaching 3 x 10(4) amperes per square centime...

We demonstrate the possibility of obtaining a rich set of self-assembled arrays from a single component cobalt nanocrystal (NC) system by a controlled variation of size, shape and inter-particle interactions. By selecting appropriate conditions in which one of a set of weak but competing interaction forces (steric, van der Waals, depletion, or magnetostatic) dominates we can reproducibly achiev...

We report a photometric study of ultra-efficient light emitting diodes (LEDs) that exhibit superior color rendering index (CRI) and luminous efficacy of optical radiation (LER) using semiconductor quantum dot nanocrystal (NC) luminophores. Over 200 million systematically varied NC-LED designs have been simulated to understand feasible performance in terms of CRI vs. LER. We evaluated the effect...

Recent advances in the synthesis of multicomponent nanocrystals have enabled the design of nanocrystal molecules with unique photophysical behavior and functionality. Here we demonstrate a highly luminescent nanocrystal molecule, the CdSe/CdS core/shell tetrapod, which is designed to have weak vibronic coupling between excited states and thereby violates Kasha's rule via emission from multiple ...

Two main synthetic strategies are used to prepare conjugated oligomer- or polymer-nanocrystal nanohybrids. In the first strategy ligand exchange is invoked to either replace with a bifunctional ligand, which contains a second functional group for coupling with conjugated oligomers or polymers (COs or CPs), or exchange for the functionalized COs or CPs in a "grafting-onto" process. Alternatively...

The 1,2,3,4-thiatriazole-5-thiolate anion (TTT(-)) was found to be a strongly binding ligand for CdSe nanocrystals, quantitatively exchanging various long-chain ligands to yield stable colloidal suspensions in common polar solvents. The TTT(-) ligand thermolyzes at <100 °C to produce thiocyanate in situ, resulting in reduced quantum confinement in nanocrystal films. CdSe(TTT) possesses far high...

This study proposes a novel HfO2 nanocrystal memory on epi-SiGe (Ge: 15%) channel. Because SiGe has a smaller bandgap than that of silicon, it increases electron/hole injection and the enhances program/erase speeds. This study compares the characteristics of HfO2 nanocrystal memories with different oxynitride tunnel oxide thicknesses on Si and epi-SiGe substrate. Results show that the proposed ...

We propose and demonstrate semiconductor nanocrystal based photovoltaic scintillators integrated on solar cells to enhance photovoltaic device parameters including spectral responsivity, open circuit voltage, short circuit current, fill factor, and solar conversion efficiency in the ultraviolet. Hybridizing (CdSe)ZnS core-shell quantum dots of 2.4 nm in diameter on multi-crystalline Si solar ce...