Electrode dimensional stability

Electrode dimensional stability must be preserved i.e., ideally, each ion should redeposit where it came from. 

The above-mentioned factors are probably not the only reasons for unstable electrode dimensional stability, and other phenomena have been proposed and confirmed to varying degrees of certainty. Included are osmotic pumping [33,34] and nonuniform current efficiencies during charging and discharging [35], Each electrode system s unique chemistry provides a further set of mechanisms to generate dimensional instability. An excellent discussion of several of these phenomena is available in Ref. 36. 

A third type of negative electrode is based on an alloy of the negative electrode active material with one or more other metals [22], Such anodes offer only limited rechargeability as the alloys lose their dimensional stability over long term cycling due to particle fracture induced by large volume changes encountered... 

Both properties contributed to reducing the energy consumption in operating the cells. With mercury cells, there is the added advantage that the dimensional stability of the new anode eliminated the continual adjustment of electrode spacing that is necessary with graphite electrodes. 

The introduction of nitrile groups into proton conductive sulfonated thermoplastics decreases their moisture absorption. Nitriles promote the adhesion of the polymers to heteropolyacids (HPA)s in composite membranes or to electrodes. In addition, the dimensional stability of the membrane is... 

CAS 12001-26-2 EINECS/ELINCS 310-127-6 Uses Filler for joint compds., adhesives, sealants, electrode coatings reinforcing agent (inc. stiffness, prevents waqting, improves dimensional stability) in thermoplastic resin composites insulator aiding dielec, props, in thermoset resin composites Features Reduces shrinkage, cracking in adhesives Properties 48 p median size bulk dens. 21 Ib/fE... 

Conductive sp -bonded diamond is being developed as an advanced catalyst support material. Boron-doped diamond thin-film electrodes possess excellent properties for this application, such as electrical conductivity, chemical inertness, extreme corrosion resistance, and dimensional stability. Compared with more commonly used sp -bonded carbon materials, diamond is highly resistant to electrochemical corrosion. For exam-... 

While the composite electrode possesses superb dimensional stability and catalytic activity, the nominal particle size is too large, at present, for a real world catalyst. We are presently pursuing pulsed deposition approaches for reducing the particle size and increasing the dispersion. For example, recent results have indicated that a series of 1-second pulses at 0.5 mA/cm results in the formation of Pt particles with a nominal diameter of ca. 50 12 nm and an estimated loading of <0.1 mg/cm. It should be possible with further work to reduce the nominal particle size to the 1-10 nm range. 

It is important to note that the combination of criteria (3) and (4) is essential for the dimensional stability of an electrode and its service life. 

Electrically conducting diamond is a new type of carlxm electrode material that is beginning to find widespread use in electroanalysis (86-88). The material possesses properties superior to other forms of carbon that include (i) low and stable background current over a wide potential range, (ii) wide working potential window in aqueous media, (iii) relatively rapid electron-transfer kinetics for several redox systems without conventional pretreatment, (iv) weak molecular adsorption, (v) dimensional stability and corrosion resistance, and (vi) optical transparency. The material is now available from several commercial sources and is not overly expensive, as commonly perceived (89). 

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