Metal particles electrochemical synthesis

The microtubular electrode concept described here also offers another possible advantage. In these concentric tubular electrodes, each particle of the Li intercalation material (the outer tube) has its own current collector (the inner metal microtubule). This could be an important advantage for Li+ intercalation materials with low electrical conductivity. This advantage was not demonstrated here because TiS2 has relatively high electronic conductivity. We have recently shown that electrochemical synthesis can be used to coat the gold microtubular current collector with outer mbes of a... 

Electrochemical Synthesis of Bimetallic Particles. Most chemical methods for the preparation of metal nanoparticles are based at first on the reduction of the corresponding metal ions with chemical reagents to form metal atoms and then on the controlled aggregation of the obtained metal atoms. Instead of chemical reduction, an electrochemical process can be used to create metal atoms from bulk metal. Reetz and Hclbig proposed an electrochemical method including both oxidation of bulk... 

In recent years, there has been a growing interest in the electrochemical synthesis of composite materials consisting of metal matrix with embedded particles of oxides, carbides, borides, etc. Metal-matrix composites offer new possibilities in fabrication of ftmctional coatings with radically improved durability and performance [1], However, in spite of the efforts of many researches, the overall picture of the processes occurring during co-deposition of metal with dispersed phase and mechanism of particle-induced modification of mechanical and chemical properties still remain unclear. In this study, we focused on the kinetics and mechanism of the electrochemical co-deposition of nickel with highly dispersed oxide phases of different nature and morphology. 

Metal nanoparticles can be prepared in a myriad of ways, e.g., by pulse radiolysis [110], vapor synthesis techniques [111], thermal decomposition of organometallic compounds [112], sonochemical techniques [113,114], electrochemical reduction [115,116], and various chemical reduction techniques. Some of the most frequently used reducing agents include alcohols [117,118], citrate [119,120], H2 [121], borohydrides [122], and, more recently, superhydride [123]. The chosen experimental conditions determine the size, size distribution, shape, and stability of the particles. Because naked metal particles tend to aggregate readily in solution, stabilizing the nanoparticles is the key factor for a successful synthesis. Sometimes the solvent can act as a stabilizer, but usually polymers and surfac-... 

The radiation method was described by Rogninski and Schalnikoff for the first time and is based on condensation of the metal atoms after collision [154]. Reetz et al. prepared nanoparticles via electrochemical synthesis [155]. Salt reduction was developed by Bonnemann to obtain mono- and bi-metallic nanoparticles in solution [156]. Salt reduction is the most widely practised method for the synthesis of colloidal metal suspensions. Faraday synthesised gold particles by the reduction of HAuCb [157]. 

It is the aim of this chapter to give an overview on both chemical and electrochemical techniques for producing metallic-particle-based CP nanocomposite materials and to outline the progress made in this field. The various synthetic approaches are organized in such a way as to present first those involving metal particle deposition in the course of polymerization, and subsequently post-polymerisation procedures that involve chemical, electrochemical, or adsorption processes (Figure 7.1). Well-established approaches, along with some newly developed techniques will be discussed, with special emphasis on those that are still underdeveloped. Synthesis of metal oxide particle-based CP composites (see e.g. [8]), as well as modification of CPs with transition-metal complexes (see e.g. [5]) remain outside the scope of this chapter. 

The involvement of pre-synthesized metal NPs in the formation of CP-based nanocomposites offers the possibility to incorporate metallic species with defined characteristics, e.g. size and stabilization shell, in the polymer material. An additional important advantage is the opportunity to achieve a homogeneous distribution of the metal particles in three dimensions that is usually not the case for metal deposition in pre-synthesized supported CPs. The synthesis of nanocomposites by means of pre-synthesized metal NPs [46-87] has been approached in several ways by carrying out electrochemical [46—59,70,71] or chemical [60-69] polymerization in their presence by simple mixing with dissolved CPs [73—76] by NPs adsorption on pre-synthesized CP layers [77-83] by layer-by-layer (LbL) adsorption using dissolved CPs [84—87] (Table 7.2, A and B). 

Yoneyama H., Shoji Y, and Kawai K., Electrochemical synthesis of polypyrrole films containing metal oxide particles, Chem. Lett, 1989, 1067-1070. 

We have demonstrated that electrochemical methods are not only a very useful tool for the synthesis and characterization of polymers, but also to study metals dispersion on polymeric matrices. This dispersion confers on diem very interesting properties for areas of tedmological interest, although a great deal of previous study and fundamental research is required particularly in the new catalyst and sensors design based on dispersed metal particles. 

There are two basic approaches to the synthesis of nanosized materials top-down or bottom-up methodologies (Table 6.2). Top-down refers to pulverization of bulk material into fine particles that can be collected as solid powder, suspended in a liquid, or deposited directly on the electrode surface. The particles are usually obtained by physical methods, such as thermal evaporation, sputtering, or laser ablation. In addition, metallic nanosized particles can also be obtained via electrochemical synthesis, exploiting the dissolution of a sacrificial anode [59]. 

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