Synthesis thiol stabilizers

Rogach, A.L., Katsikas, L., Kornowski, A., Su, D., Eychmuller, A., and Weller, H. (1996) Synthesis and characterization of thiol-stabilized CdTe nanocrystals. Ber. Bunsenges. Phys. Chem. 100, 1772-1778. 

This section is divided into two main subsections. The first describes the synthesis and characterization of phosphine-stabilized gold clusters. The second focuses on the synthesis and characterization of thiol-stabilized gold clusters and the study of other stabilizers such as arsines or boranes are described. 

In addition to chemical methods variety of physical methods has been employed for the synthesis of AuNPs. UV irradiation is used to improve the quality of the AuNPs when it is used in synergy with micelles or seeds [32,33], Near-IR laser irradiation provokes an enormous size growth of thiol-stabilized AuNPs [34], The presence of an ultrasonic field (200 kHz) allowed the control of the rate of AuC14" reduction in an aqueous solution containing only a small amount of 2-propanol and the sizes of the formed AuNPs are controlled by varying the parameters such as the temperature of the solution, the intensity of the ultrasound, and the positioning of the reactor [35,36], Sonochemistry was also used for the synthesis of AuNPs within the pores of silica and for the synthesis of Au/Pd bimetallic particles [37,38], Radiolysis has been used to control the size of AuNPs [39], Laser photolysis has been used to form AuNPs in block copolymer micelles. Laser ablation is another technique of AuNP synthesis that has been used under various conditions whereby size control can be induced by the laser [40,41],... 

Thiol stabilization also proved to offer a very successful route towards the creation of monosized nanoparticles of various compounds however, as it has also attracted widespread interest it will be outlined separately in Chapter 3.2.1.2. In this chapter, from this point onwards, attention will be focused on recent developments that differ from the hot injection synthesis and from the thiol technique. 

The Brust—Schiffrin Method Two-Phase Synthesis and Stabilization by Thiols... 

THE BRUST-SCHIFFRIN MFTHOD TWO-PHASE SYNTHESIS AND STABILIZATION BY THIOLS ... 

Rogach AL, Komowski A, Gao MY, Eychmuller A, Weller H (1999) Synthesis and characterization of a size series of extremely small thiol-stabilized CdSe nanocrystals. J Phys Chem B 103 3065... 

M. Brust synthesis of thiol-stabilized gold nanoparticles... 

A.L. Rogach, L. Katsikas, A. Komowski, D. Su, A. Eychmuller, H. Weller, Synthesis and Characterization of Thiol-Stabilized CdTe Nanocrystals, Ber. Bunsenges. Phys. Chem. 100 (1996) 1772-1778. 

The cycloaddition of alkynes with the tributylphosphine-carbondisulfide adduct 131 results in the in situ formation of the ylides 132 which react with aldehydes to give the novel 2-arylidene or 2-alkylidene-l,3-dithioles 133 (Scheme 36) [132]. Concerning ylides C-substituted by sulfur we can also mention a publication on the behavior of various keto-stabilized ylides towards acyclic and cyclic a s-disulfides allowing the synthesis of substituted thiazoles, thiols, and dithiols [133]. 

Although most of the structurally characterized gold clusters are phosphine-based systems, in recent years some studies have focused on the synthesis of gold clusters with other stabilizers coexisting with phosphines such as thiols, arsines and boranes. Certain heteroleptic gold clusters stabilized with these ligands and arylphosphines in the same molecule have been structurally characterized. 

Although thiol ligands are the most widely used as stabilizers in the synthesis of Au NPs, other organic ligands bearing amine, phosphine, phosphine oxide, carboxylate or other functional groups have been employed alone or in mixtures. 

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