Other Metal Nanoparticles

The solvent-free controlled thermolysis of metal complexes in the absence or presence of amines is the simple one-pot synthesis of the metal nanoparticles such as gold, silver, platinum, and palladium nanoparticles and Au-Ag, Au-Pt, and Ag-Pd alloy nanoparticles. In spite of no use of solvent, stabilizer, and reducing agent, the nanoparticles produced by this method can be well size regulated. The controlled thermolysis in the presence of amines achieved to produce narrow size dispersed small metal nanoparticles under milder condition. This synthetic method may be highly promising as a facile new route to prepare size-regulated metal nanoparticles. Finally, solvent-free controlled thermolysis is widely applicable to other metal nanoparticles such as copper and nickel... 

In particular, silver nanoparticles and occasionally gold nanoparticles are employed in inks due to their low electrical resistivity, low tendency toward oxidation, and generally high chemical stability. Other metal nanoparticles, such as copper and nickel particles, tend to oxidize and yield formulations that are less stable than silver and gold at ambient conditions. Carbon nanoparticles, which incorporate relatively inexpensive raw materials, are difficult to prepare in an industrial process and have higher resistivity than metal particles. Use of non-metal nanoparticles, such as silicon, for non-conductive electronic features, is also described in the literature on IJ inks. ... 

Except gold, several other metal nanoparticles, also those of less noble metals, could be prepared, for instance, of silver, palladium, and cobalt, as well as sulfidic species like CdS or PbS. ... 

AuNPs in Liquid-State Environment Solute pure and monolayer-coated ( capped ) AuNPs are central targets in colloid and surface science also with a historical dimension [258-262]. Facile chemical syntheses introduced by Schmid et al. [260] and by Brust et al. [263] have boosted AuNP and other metal nanoparticle science towards characterization of the physical properties and use of these nanoscale metallic entities by multifarious techniques and in a variety of environments. Physical properties in focus have been the surface plasmon optical extinction band [264—269], scanning and transmission electron microscopy properties, and electrochemical properties of surface-immobilized coated AuNPs [173, 268-276], To this can be added a variety of AuNP crosslinked molecular and biomolecular... 

Theranostic nanoparticles with gold can be made with other metallic nanoparticles such as SPIONs, for providing multi-imaging modality and dual therapeutic outcomes. A recent study showed that gold and SPIONs loaded in an amphiphilic diblock copolymer PEG-fo-PCL had selective tumor accumulation, enabling MRI of the tumor margins and improved survival rate of tumor-bearing mice after NIR irradiation [82]. 

While they are not strictly redox-containing dendrimers. Crooks and Zhao have encapsulated platinum and other metallic nanoparticles inside PAMAM dendrimers. The catalytic properties of these materials have been examined using cyclic voltammetry, and it was found that a gold electrode, modified with large hydroxyl-terminated PAMAM dendrimers containing clusters of 60 platinum atoms, was readily able to catalyze O2 reduction [98]. Similar results have been reported for palladium clusters encapsulated in the same hydroxyl-terminated PAMAM dendrimers [99]. 

This methodology has been employed to attach many functional groups onto other metal nanoparticles, including amines and carboxylic acid groups. ... 

A similar oxidation process was observed for the other metal nanoparticles produced via RESOLV. For example, when a PVP polymer-stabilized suspension of Ag nanoparticles was purifled via dialysis against freshwater, the UV-vis absorption spectrum was signiflcanfly altered (Figure 34). Gradual disappearance of the plasmon absorption band was probably due to the oxidation of the Ag nanoparticles (263). Similarly, oxidation of Cu nanoparticles in a suspension was evidenced by the suspension color changing gradually from dark yellow to blue (263). 

Texhle Finishing Using Other Metal Nanoparticles 548... 

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