Electrical Resistance Of Platinum Research Articles

Cathodic arc deposition of nanocrystalline titanium nitride thin film on fluorine doped tin oxide coated glass substrate: Crystal structural, microstructural, mechanical, optical and electrical properties

The nanocrystalline titanium nitride (TiN) films were deposited on fluorine doped tin oxide (FTO) coated glass substrates for the first time by cathodic arc deposition. The crystalline phase and orientation, growth morphology, surface roughness, hardness, scratch adhesion, electrical resistivity, optical absorption and bandgap of the TiN films were investigated. The GI-XRD confirmed the formation of cubic TiN and crystallographic orientation growth. The 2150 nm thick TiN film showed (111) orientation due to columnar growth patterns, while the 650 nm TiN film formed with the (200) orientation. The grain size of TiN films was 50–200 nm by FESEM and AFM analyses, and it was formed as elongated nanocrystals of 65–125 nm width and 120–250 nm lengths. The microhardness of the 650, 1000 and 2150 nm TiN thin films was measured to be 836, 943 and 1281 HV0.05 respectively. The scratch adhesion test demonstrated a good adhesive strength up to a critical load of 10 N and beyond the delamination occurred. The electrical resistivity of TiN film found to vary with thickness, the 650 nm TiN film showed a low resistivity of 16 × 10-6 Ω cm, which is comparable with the electrical resistivity of platinum and magnetron sputtered TiN film. The UV-Vis-NIR diffused reflectance spectroscopic studies of the TiN thin film showed a sharp absorption at 448 nm due to plasmon absorption and Tauc plot showed direct band gap of 2.1 eV. The results demonstrated that cathodic arc deposited nanocrystalline TiN thin film deposited on FTO glass substrate can be used as counter electrode for dye sensitized solar cell (DSSC) applications.

Evaluation of self-heating effect in platinum resistance thermometers

The electrical resistance of Platinum (Pt) metal wire is used as thermometric property because of its high sensitivity to temperature with a positive temperature coefficient. Self-heating is a well-known effect in resistance thermometry occurred due to Joule heating in the sensing element. The importance of self-heating correction in temperature measurement and its value for different types of platinum resistance thermometers (PRTs) were investigated and evaluated in this work. We studied the factors affecting the self-heating correction of PRT such as, the amount of current flow, resistance of Pt wire, construction of PRT, thermal contact medium and operating temperature. The heat dissipation is influenced by construction of PRT as it depends on thermal conductivity of gas filled in sheath, sheath material, and method of winding of Pt wire on electric insulator. The paper provides a detailed interpretation of factors influencing the self-heating correction value of PRTs.

Electrical resistance of platinum at a pressure of up to 1 GPa

The effect of a high hydrostatic pressure of up to 1 GPa on the electrical resistance of platinum in the 20–100°C temperature range is investigated. An approximate formula is proposed for correcting the readings of platinum resistance thermometers used in a medium under high hydrostatic pressures.

The size effect in electrical resistivity of platinum

The size effect in electrical resistivity of platinum

Measurements of the thermal conductivity and electrical resistivity of platinum from 100 to 900 C

Abstract : Measurements were made of the thermal conductivity and the electrical resistivity of commercial grade platinum (99.987 per cent pure) in the temperature range 373 to 1373K. The measurements were made with a view to providing accurate data on the thermal conductivity of platinum to serve as a basis for establishing platinum as a thermal conductivity standard reference material. The data obtained agree within experimental error and show the thermal conductivity of platinum to be a smoothly increasing function of temperature in the measured range. The data are considered to be accurate to better than one percent.

The electrical resistance of platinum at repeated quenching

It is shown how the irreversible change in electrical resistance of platinum is related to the irreversible change in resistivity and dimensional changes of the samples. A preliminary interpretation is also given of the component connected with resistivity on the basis of the scattering of conduction electrons on defect formations produced mainly from the vacancies and stabilized by impurities, primarily oxygen.

The Thermal Conductivity and Electrical Resistivity of Platinum

The Thermal Conductivity and Electrical Resistivity of Platinum

The electrical resistance of platinum at repeated quenching

The electrical resistance of platinum at repeated quenching

Change of platinum resistance by hydrogen

The change of electrical resistance of platinum in contact with neutral and electrically excited hydrogen, air and argon was studied. Even a trace of hydrogen was sufficient to cool the glowing wire. Influence of ageing and gas pressure showed a marked decrease in the wire resistance. Air and argon showed no appreciable effect on the wire resistance even at higher temperatures.

THERMAL AND ELECTRICAL CONDUCTIVITY OF RHODIUM, IRIDIUM, AND PLATINUM

Measurements are reported of the thermal and electrical conductivities of the transition elements Rh, Ir, Pt in a state of high purity; the rapid rate of decrease of the "ideal" thermal and electrical resistivities with temperature, particularly in Rh and Ir, suggests that s–d transitions are not a dominant resistive mechanism at low temperatures in these metals, in contrast to palladium, iron, and nickel, which were studied previously. The electrical resistivity of platinum is in general agreement with the earlier results of de Haas and de Boer (1934); the quadratic dependence on temperature observed below about 10° K. suggests that electron–electron collisions may well be an important factor in this metal.

Electrical Resistance of Platinum at High Temperatures

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The electrical resistance of platinum at low temperatures

Summary The electrical resistance of very pure platinum has been investigated at very low temperatures. As a result it is found impossible to represent the experimental data by a simple formula [ R / R 0°C· ] = AT B [Houston [ R / R 0 ] = AT 2 Bloch, Peierls, [ R / R 0°C· ] = AT 5 )], nor does the more complicated formula of Vonsovsky and Smirnov ([ R / R 0°C· ] = C 1 T 5 + C 2 T 4 + C 3 T 3 ) agree with our results.