Platinum future applications

Introduction Biologic Background Platinum Imaging Techniques Conclusion and Future Applications... 

Chemically modified electrodes have been used in place of the conventional materials (e.g., platinum) to modify the electron-transfer rates (Heineman and Kissinger, 1978 Kissinger, 1974, 1976). Polymers have also recently been used in this application (Miller and Van de Mark, 1978). It is expected that future applications of these electrodes will include applications in synthetic-scale organic chemistry. 

Trace impurities in noble metal nanoclusters, used for the fabrication of highly oriented arrays on crystalline bacterial surface layers on a substrate for future nanoelectronic applications, can influence the material properties.25 Reliable and sensitive analytical methods are required for fast multi-element determination of trace contaminants in small amounts of high purity platinum or palladium nanoclusters, because the physical, electrical and chemical properties of nanoelectronic arrays (thin layered systems or bulk) can be influenced by impurities due to contamination during device production25 The results of impurities in platinum or palladium nanoclusters measured directly by LA-ICP-MS are compared in Figure 9.5. As a quantification procedure, the isotope dilution technique in solution based calibration was developed as discussed in Chapter 6. 

The sole example of a silicon-platinum cluster is the compound in entry 24 its structure has been noted in Section IV,A. It seems very likely that many further cluster systems await discovery, particularly with iridium, platinum, and gold, and that this represents an important future area of research. One obvious application is as precursors to metal silicides with high metal silicon ratios using c.v.d. techniques (compare Section V,A). 

Each category, by itself, can be a topic for a separate symposium, and it is hoped that in the future such symposia will be forthcoming. The topics chosen were such that they would cover a broad area of the chemistry of platinum group metals. The session on industrial aspects was included to enable scientists in industry to present their views on the problems that are facing the industry and perhaps stimulate sufficient interest so that newer applications could be developed in the future. It is also hoped that such a forum would enable scientists in industry to summarize broadly the work carried out by them without worry about violation of proprietary nature of the work. 

In this review, the synthesis, properties, and applications in optoelectronic fields of polyfluorenes with on-chain metal centers have been briefly summarized. Metal complexes involving iridium(III), platinum(II), europium(III), rhenium(I), and ruthenium(II) complex coupled with polyfluorene are surveyed. Efficient energy transfer from polymer main-chain to metal-centers can occur in these host-guest systems. These kinds of novel polymers are usually applied in the fields of phosphorescent OLEDs, memory devices, and sensors. In particular, the realization of efficient energy transfer and phosphorescence offers a huge potential for future optoelectronic devices based on these kinds of materials. 

Since Pt dissolution is favored by high electrode potential, relative humidity, and temperature, the possibility to limit the risk of electrocatalyst aging is based on the use of Pt-alloy catalyst instead of pure platinum, at least for the cathode, which is characterized by higher potential with respect to anode, and by adoption of operative conditions not too severe in terms of humidity and temperature. While this last point requires interventions on the membrane structure, the study of catalyst materials has evidenced that a minor tendency to sintering can be obtained by the addition of non-noble metals, such as Ni, Cr, or Co, to the Pt cathode catalyst [59, 60], suggesting a possible pathway for future work. On the other hand also the potential application of non-platinum catalysts is under study, in particular transition metal complexes with structures based on porphyrines and related derivatives have been proposed to substitute noble metals [61], but their activity performance is still far from those of Pt-based catalysts. 

The ELM pertraction technology has good potential for more applications at industrial scale in the near future. The industries in question might include metal mining and refinery operations (precious metals and platinum group metals are good examples), tannery industry (recovery of hexavalent chromium), and processing of nuclear wastes (recovery of uranium, strontium, and other metals). 

The PE MFC has a solid ionomer membrane as the electrolyte, and a platinum, carbon-supported Pt or Pt-based alloy as the electrocatalyst. Within the cell, the fuel is oxidized at the anode and the oxidant reduced at the cathode. As the solid proton-exchange membrane (PEM) functions as both the cell electrolyte and separator, and the cell operates at a relatively low temperature, issues such as sealing, assembly, and handling are less complex than with other fuel cells. The P EM FC has also a number of other advantages, such as a high power density, a rapid low-temperature start-up, and zero emission. With highly promising prospects in both civil and military applications, PEMFCs represent an ideal future altemative power source for electric vehicles and submarines [6]. 

These disadvantages may all be avoided, and are in fact considerably reduced by the use of lead instead of platinum wire, but a simpler procedure is still desirable. The problem of establishing the variation of specific heat for a large number of substances as completely as possible is extremely important, both in the light of any future theory of the solid state, which will apparently be developed from a consideration of low-temperature properties, and also in view of the applications of our Heat Theorem and the study of chemical affinity. 

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