Platinum electrical properties

CNTs offer an exciting possibility for developing ultrasensitive electrochemical biosensors because of their unique electrical properties and biocompatible nanostructures. Luong et al. have fabricated a glucose biosensor based on the immobilization of GOx on CNTs solubilized in 3-aminopropyltriethoxysilane (APTES). The as-prepared CNT-based biosensor using a carbon fiber has achieved a picoamperometric response current with the response time of less than 5 s and a detection limit of 5-10 pM [109], When Nation is used to solubilize CNTs and combine with platinum nanoparticles, it displays strong interactions with Pt nanoparticles to form a network that connects Pt nanoparticles to the electrode surface. The Pt-CNT nanohybrid-based glucose biosensor... 

The eight-coordinate vanadium complex V(S2CMe)4 contains both dodecahedral and square prismatic eight-coordinate molecules in the same crystal.322 Of particular interest is the chain-like, mixed valence platinum complex [Pt2(S2CMe)4( i-I)]A, which displays unusual electrical properties metallic conduction between 300 and 340 K and semiconducting properties below 300 K,323 whereas the analogous nickel complex, [Ni2(S2CMe)4(p-I)]x is a semiconductor.324... 

Very few dithiolene platinum complex-based compounds have been reported and most of them exhibit poor electrical conductivity (9, 122, 123). The complex (Me4N)[Pt(dmit)2]2 does show metal-like behavior (RT conductivity = 10 S cm 1) but only >220 K (123). Another exception is (NHMe3)[Pt(dmit)2]3. This compound, which has the unusual 1 3 stoichiometry, behaves as a metal down to 180 K, with a room temperature conductivity of 140 S cm-1 (91). The Pt(dmit)2 units form pairs with an eclipsed overlap mode. Unlike the analogue Ni derivatives (see above) substituting one hydrogen atom for one methyl group in the (Me4N)+ cation leads to an improvement in the electrical properties. 

Membrane structures that contain the visual receptor protein rhodopsin were formed by detergent dialysis on platinum, silicon oxide, titanium oxide, and indium—tin oxide electrodes. Electrochemical impedance spectroscopy was used to evaluate the biomembrane structures and their electrical properties. A model equivalent circuit is proposed to describe the membrane-electrode interface. The data suggest that the surface structure is a relatively complete single-membrane bilayer with a coverage of 0.97 and with long-term stability/... 

Recently, the crystal structure of Pt ClaCbipy) (bipy = bipyridyl) has been reported (542, 567). The structure of the dichroic red phase of this diamagnetic complex reveals a one-dimensional stack with the interplanar and platinum-platinum spacings of 3.40 and 345 A, respectively. Similarly, c -dichlorodiammineplatinum(II) forms one-dimensional chains in the solid with alternating noncollinear platinum-platinum spacings of 3.409 and 3.372 A (535). The electrical properties of PtCl2(bipy) and w-PtCl2(NH3)2 have not been reported. 

Coagulation of the platinum particles takes place during the electroplating process. Particles with diameter less than 10 nm coagulate during the reduction and eventually grow to 50-100 nm as illustrated in Fig. 2.17. In this model it is assumed that the coagulated platinum particles are spherical and conserve the electrical properties of platinum. Also, the particles are assumed to have the same size. Illustration on Fig. 2.18 shows the piled particles model and how the particles are in contact with each other. 

Gray, J. A. B. and Svaetichin, G., 1951, Electrical properties of platinum-tipped microelectrodes in Ringer s solution, Acta Physiol. Scand. 46 278-284. 

The electrical properties of a material can be determined from the complex impedance of a cylindrical capacitor filled with this material. Two (platinum coated) alumina cylinders define a capacitor gap of 5 mm width and 60 mm inner diameter. The height of the cylinders is 80 mm. The electrodes of the capacitor gap are made of platinum, which is burned onto the alumina at 1350 °C. 

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