Platinum composite electrodes

Platinum auxiliary electrode, (model 52-67 1, Crison, Spain) double junction Ag/AgCl reference electrode (Orion 900200) and magnetic graphite composite electrode (M-GECE) as working electrode. 

Secondary pH reference materials can be derived from the PS buffer solutions by different measurement procedures, which provide results for pH(SS) of the same nominal composition as pH(PS) pH(SS) of different composition pH(SS) not compatible with platinum hydrogen electrodes. 

Figure 10. A polymeric composite electrode. PAN (Polyaniline), PP (polypyrrole) and R (Platinum).

A three-electrode cell (a BAS VC-2 10-mL glass electrochemical cell) consisting of a platinum wire counter electrode (BAS MW-1032), a BAS MF-2063 Ag/AgCl/3M KC1 reference electrode, and the corresponding composite electrode as the working electrode, was used. All experiments were performed at room temperature. 

For fabrication of a full plastic DSSC, the plastic counter electrode needs to show high performance in keeping with a high-density photocurrent, with characteristics close to those of a platinum counter electrode. 1-V characteristics of plastic DSSCs have been examined. An electrolyte composition of 0.4M Lil, 0.4M TBAI, 0.04M I2, and 0.3 M N-methylbenzimidazole (NMB) in acetonitrile (AN)/MPN (1 1 by volume) was used and N719 as a dye sensitizer of the Ti02 photoanode the 1-V curves are compared in Figure 3.7 for PEDOT-PSS-based counter electrodes and a standard platinum sputtered electrode [29]. 

J. Li and X. Lin, A composite of polypyrrole nanowire platinum modified electrode for oxygen reduction and methanol oxidation reactions, J. Electrochem. Soc., 154, B1074— B1079 (2007). 

Electrochemical oxidation of methanol is important for application in direct methanol fuel cells. Among metal catalysts, platinum is generally used as an electrocatalyst for such an oxidation. However, it suffers from poisoning by CO, formed as a by-product, and other adsorbed species. A promising way to enhance electrocatalytic activity of Pt and reduce its poisoning effect is to fabricate conducting polymer/Pt composite electrodes. 

Being in the nanotechnology era, novel nanostructured composite materials are expected to be designed showing improved properties due to nanostructuration. Moreover, composite electrodes from expensive metals (gold, platinum, etc.) can be prepared using the NPs as conductive fillers, with enhanced properties but at lower prices compared to their pure conductor counterparts. 

Chartarrayawadee, W., Moulton, S. E., Li, D., Too, C. 0., and Wallace, G. G. [2012]. Novel composite graphene/platinum electrocatal3dic electrodes prepared by electrophoretic deposition from colloidal solutions, Electrochim. Acta, 60, pp. 213-223. 

Most biosensors described in the literature for the determination of urea are potentiometric based on NH4 or HCOj" sensitive electrodes [181, 182]. Osaka and co-workers constructed a highly sensitive and rapid flow injection system for urea analysis with a composite film of electropolymerised inactive PPy and a polyion complex [183]. Pandey and co-workers fabricated a urea biosensor based on immobilised urease on the tip of an ammonia gas electrode (diameter 10 pm) made from a PPy film coated onto a platinum wire [170]. The enzymatic response was achieved in the wide range of 0.001-0.05 M with a stability of more than 32 days. Cho and co-workers [184] developed a procedure for urea determination by crosslinking urease onto PANI-Nafion composite electrodes, which could sense the ammonium ions efficiently. Such a urea biosensor has a detection limit of about 0.5 pM and a response time of 40 seconds. 

The OCPs for the Pt/diamond composite electrodes with varying platinum loadings were measured in nitrogen-saturated methanol -1-0.1... 

Cui HF, J. S. Ye, W. D. Zhang, J. Wang, F. S. Sheu. Electrocataljhic reduction of oxygen hy a platinum nanoparticle/carbon nanotuhe composite electrode. J Electroanal Chem 2005 577 295-302. 

Wang J, Swain GM. Fabrication and evaluation of platinum/diamond composite electrodes for electrocatalysis. J Electrochem Soc 2003 150 E24-32. 

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