Passivation, nanocrystals

Flarfenist S A and Wang Z L 1999 Fligh-temperature stability of passivated silver nanocrystal superlattices J. Phys. Chem. B 103 4342... 

Gorer S, Ganske JA, Hemminger JC, Penner RM (1998) Size-selective and epitaxial electrochemical/chemical synthesis of sulfiir-passivated cadmium sulfide nanocrystals on graphite. J Am Chem Soc 120 9584-9593... 

Myung, N., Bae, Y. and Bard, A. J. (2003) Enhancement of the photoluminescence of CdSe nanocrystals dispersed in CHCI3 by oxygen passivation of surface states. Nano Lett., 3, 747—749. 

Guzelian AA, Katari JEB, Kadavanich AV, Banin U, Hamad K, Juban E Alivisatos AP, Wolters RH, Arnold CC, Heath JR (1996) Synthesis of size selected, surface passivated InP nanocrystals. J Phys Chem B, 100 7212-7219... 

Zehner RW, Lopes WA, Morkved TL, Jaeger H, Sita LR. Selective decoration of a phase-separated diblock copolymer with thiol-passivated gold nanocrystals. Langmuir 1998 14 241-244. 

A transient optical absorption study of charge recombination dynamics was recently reported on CD CdS with a crystal size of 5 nm (no details of the deposition were provided) [35]. Three different time constants for the decay of the transient absorption bleaching were measured (0.8 psec, 17 psec, and 800 psec) and were attributed to three groups of nanocrystals with specific defects. Tri-octylphosphine oxide (TOPO), a well-known passivating agent for CdSe nanocrystals that acts by binding to Cd, was found to increase the relative contribution of the 800-psec recombination, which was therefore attributed to volume recombination, since the TOPO is expected to reduce the relative contribution of surface recombination (represented by the two shorter time constants). 

In a Si zero-dimensional system the strong quantum confinement can increase the optical infrared gap of bulk Si and consequently shift the optical transition energies towards the visible range [65,66]. This is the reason for which silicon nanocrystals (Si-NCs) with a passivated surface are used as the natural trial model for theoretical simulations on Si based light emitting materials, such as porous Si or Si nanocrystals dispersed in a matrix. In this section we present a comprehensive analysis of the structural, electronic and optical properties of Si-NCs as a function of size, symmetry and surface passivation. We will also point out the main changes induced... 

In one recent study, Mn2+-doped CdS nanocrystals grown with a ZnS passivating shell were used as the recombination centers in direct current (dc) electroluminescent devices (104). The Mn2+ CdS/ZnS nanocrystals were prepared by the inverse micelle procedure (102) (see Section II.C) and these colloids were incorporated into a multilayer device structure by spin-coat... 

Cysteine has also been shown to passivate the surface of highly fluorescent CdS bionanocrystallites. These nanocrystals have been of interest owing to their possible use as fluorescent labels and photocatalysts. Generally, the nanoparticles were formed by the addition of inorganic sulfide (Na2S) to solutions of a cadmium cysteine precursor complex. This synthetic process yielded nanocrystals of a size dimension between 2 and 4 nm in diameter. ... 

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