Synthesis seed-mediated

Growth using citrate-seeds w/o Ag Growth using CTAB-seeds w/ Ag+  

Figu ren.18 Schematic of three-dimensional morphology of gold nanorods prepared using (a) citrate-capped seeds without kg (b) CTAB-capped seeds in the presence of Ag. Reproduced with permission from Ref [122] 2006 American Chemical Society. 

CTAB micelle-AuCl2 (0.1M CTAB, 5x10 M HAUCI4) 

CTEAB has also been used as a stabiUzing agent to grow Au bipyramids [133]. 

The SPR wavelengths of the resultant bipyramids can be varied from 700 to llOOnm by changing the amount of seeds, relative to that of the Au precursor. 

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There have been many recent studies in support of this mechanistic approach. Stepwise reductive formation of Ag3+ and Ag4+ clusters has been followed using spectroscopic methods by Henglein [33], Reduction of copper (II) to colloidal Cu protected by cationic surfactants (NR4+) through the intermediate Cu+ prior to nucleation of the particles [36] as monitored by in situ x-ray absorption spectroscopy is another example. The seed-mediated synthesis also serves as evidence in support of this mechanism [38-41],... 

Gole, A. and Murphy, C. J. (2004). Seed-mediated synthesis of gold nanorods Role of the size and nature of the seed. Chem. Mater. 16 3633-3640. 

Smith, D. K. and Korgel, B. A. (2008). The importance of the CTAB surfactant on the colloidal seed-mediated synthesis of gold nanorods. Langmuir 24 644-649. 

Scheme 7.1 Seed-mediated synthesis of gold nanorods. The seeds are prepared in step I. A stock solution is prepared in step II and the protocol for nanoiod synthesis is shown in step III. (Reprinted with permission from C. J. Murphy et al. J. Phys. Chem. B 2095, 109, 13857. Copyright (2005) American Chemical Society.)...

Seed-mediated synthesis of the core followed by chemical deposition (e.g. using a mild reducing agent)... 

H. Y. Wu et al.. Seed-mediated synthesis of high aspiect ratio gold nanorods with nitric acid. Chemistry of Materials, 17(25), 6447-6451 (2005). 

Berhault, G., M. Bausach, L. Bisson, L. Becerra, C. Thomazeau, and D. Uzio. 2007. Seed-mediated synthesis of Pd nanocrystals Factors influencing a kinetic- or thermodynamic-controUed growth regime. J. Phys. Chem. C 111 (16) 5915-5925. 

I 7 7 Spherical and Anisotropic Noble Metal Nanomaterials 11.2.3.3 Seed-Mediated Synthesis... 

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