Quantum dots trioctylphosphine oxide

Considerable practical difficulties arise in making quantum dots of a regular size and shape, and in preventing the dots, once made, from coalescing into a larger crystal. CdSe quantum dots are currently made by dissolving selenium and dimethylcadmium ((CH3)2Cd) in hot trioctylphosphine oxide (TOPO), from whence large quantities of CdSe... 

Quantum dots used in liquid crystal systems (ranging in size from a few to tens of nanometers) are usually from the II-VI group, and include CdS, CdSe, and CdTe capped with trioctylphosphine/trioctylphosphine oxide (TOP/TOPO) [101-103], CdS as well as CdTe stabilized with thiols [104], and CdSe protected with amines [105]. 

This technique is widely used for the fabrication of quantum dots. This can be illustrated by the preparation of near-monodisperse semiconductor CdSe nanocrystallites with diameters ranging from 1.2 to 11.5 nm by rapid injection of organometallic reagents (dimethylcadmium and tributylphosphine selenide) into a hot coordinating solvent (trioctylphosphine oxide) that acts as a capping agent [40]. This reaction can be carried out in macroscopic quantities in a single step. 

Trioctylphosphine oxide (TOPO) caps are used in quantum dots for LEDs moreover, the CdSe cores of these quantum dots can be obtained directly from cadmium selenide complexes as (12.401) [18,19]. Both TOPO and TOP can be used to produce various nanocrystals [20,21], Quantum dots of InP and GeP are being explored [22,23], Nickel nanoparticles, stabilised by TOPO, have been converted to Ni2P nanoparticles by the action of white phosphorus [21]. Highly luminescent nanocrystals of InP have been obtained. 

Fig. 4 Colloidal synthesis of CdSe quantum dots. TOP trioctylphosphine, TOPO trioctyl-phosphine oxide. Reprinted from [126], Copyright 2004, with permission from Elsevier...

Air-Stable and highly active dendritic phosphine oxide-stabilized palladium nanoparticles were prepared and applied in catalytic reactions Ligand exchange reactions at the surface of trioctylphosphine oxide-capped CdS quantum dots haver been studied using attenuated total reflection (ATR) IR spectroscopy ... 

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