Seed-assisted synthesis

C. Kong, T. Shintani, T. Tsuru, Pre-seeding -assisted synthesis of a high performance polyamide-zeolite nanocomposite membrane for water purification, New Journal of Chemistry 34 (2010) 2101-2104. 

Xiao and coworkers first reported the organic-template-free and fast synthesis route for Beta zeolite by seed-assisted synthesis [32]. The calcined Beta zeoUte seeds with particle sizes of 60-100nm were added to the aluminosilicate gel with a molar ratio of SiO Al Oj Na O ... 

Recently, Okubo and coworkers built a working hypothesis in seed-assisted synthesis without organic templates, which may provide a new idea for synthesis and broaden framework types of zeolites [40]. By analyzing the examples of the seed-assisted and organic-template-free synthesis of zeolites in detail, they concluded that the composite building units that both the frameworks of zeolite seeds and the crystallized zeolites contained were the key to the organic-template-free synthesis. 

Itabashi K, Kamimura Y, lyoki K, Shimojima A, Okubo T. A working hypothesis for broadening framework types of zeolites in seed-assisted synthesis without organic structure-directing agent J Am Chem Soc 2012 134 11542-9. 

A seed-assisted chemical reaction at 368 K is found to yield uniform, straight, thin single-crystalline ZnO nanorods on a hectogram scale,181 Zinc oxide nanowires have been synthesized in large quantities using plasma synthesis.1 Variable-aspect-ratio,... 

Lie Ken Jie, M.S.F., M.K. Pasha, and F. Ahmad, Ultrasound-Assisted Synthesis of San-talbic Acid and a Smdy of Triacylglycerol Species in Santalum album (Linn.) Seed Oil, Lipids 31 1083-1089 (1996). 

A variety of solution methods such as seed-assisted growth, template-based synthesis, polyol method, solvothermal method and oriented attachment have also been developed for the synthesis of one-dimensional nanostructures. Here we will present various examples of the nanowires including metals, oxides, chalcogenides and pnictides with different synthetic methods. 

There are a lot of other methods for QDs synthesis such as microwave-assisted synthesis, cation-exchange-based synthesis, " seeded synthesis," polymer-templated synthesis, and a top-down approach. These methods could serve as alternatives to the conventional methods of preparing QDs with the desired properties, especially for those that are diffieult to prepare... 

Scheme 2 Schematic of a seed-mediated, surfactant-assisted gold nanorod synthesis. The small black dots represent Ag+ ions, the orange stars are CTAB molecules forming micelles, the yellow circles and green squares are AuCLf and AuC12 , respectively, forming complexes with the CTAB micelles. Freshly-prepared gold nanoparticle seeds are injected into the growth solution in the final step of the nanorod synthesis [166]. (Copyright 2008, American Chemical Society)...

In order to accelerate the synthesis of both zeolite seeds and membranes, microwave-assisted hydrothermal synthesis (MW-HT) revealed an attractive method. Colloidal zeolite seeds can be successfully prepared by MW-HT synthesis [100,112,113]. Starting from a seeded support,... 

A detailed study of the growth process and the structural evolution of silicalite-1 (MFI) films was undertaken with the aid of grazing incidence synchrotron X-ray diffraction. [65] The diffraction data of the adsorbed and grown zeolite films at different incident and exit angles reflect the distribution of the crystal orientation along the film thickness. The films were prepared via assisted adsorption of nanoscale MFI seed crystals, followed by calcination and subsequent hydrothermal synthesis on the seed layers. The adsorbed (multi-) layer of seed crystals consists of randomly oriented crystals. With progressing hydrothermal growth, the film surface becomes smoother and a preferred crystal orientation with the b-axis close to vertical to the substrate develops. 

Harpeness et al. reported the synthesis of roughly spherical Au-Pd core-shell NCs by the MW-polyol-assisted simultaneous reduction of gold and palladium salts. In this case the largely different Au + or Au+ and PdJ redox potentials firstly ensured gold reduction and the formation of metal seeds which in turn promoted heterogeneous nucleation of Pd [255] (Fig. 10.11a). In a similar fashion Pd-Pt core-shell NCs consisting of cubic Pd NC evenly decorated by Pt pellets was very recently described [256] (Fig. 10.11b). 

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