Bimetallic Sensor Research Articles

Amperometric non-enzymatic bimetallic glucose sensor based on platinum tellurium microtubes modified electrode

A non-enzymatic amperometric sensor for glucose detection based on a Pt electrode modified with Te microtubes (Te-MTs), by direct drop casting of Te-MTs dispersed in ethanol, is proposed. The spectroscopic characterization of as synthesized Te-MTs and Pt/Te-MTs modified electrodes was performed by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Moreover electrochemical characterization of Pt/Te-MTs modified electrodes was performed by Cyclic Voltammetry (CV) and Cronoamperometry (CA) in phosphate buffer (pH=7 I=0.2). Electrochemical results indicate that the proposed sensor exhibits very strong and sensitive amperometric responses to glucose and explains a good anti-interference ability.

Effect of aging on optical properties of bimetallic sensor chips

Bimetallic silver/gold sensor chips are attractive since they combine the advantages of both silver and gold layers. Optical properties of the bimetallic sensor chips show significant aging effects. Surface plasmon resonance (SPR) curves were produced on an SPR device and the time dependence of aging on SPR curves was studied. The results show that resonance angle and full width at half maximum (FWHM) of response curves increase with the aging time after film deposition. The performance of the sensor chips in terms of intrinsic sensitivity (IS) degrades with aging time. The underlying mechanism of the aging effect is explained as the growth of a silver oxide layer between gold and silver during the aging process.

A novel temperature-compensating structure for micromechanical bridge resonator

A novel temperature-compensating structure for micromechanical bridge resonators has been developed in this paper. The temperature drift of resonance frequency is compensated by the output voltage of a Si/SiO2 bilayer cantilever temperature sensor, which is integrated in the same chip with the bridge resonator. The mechanism of this kind of temperature sensor resembles that of commercial bimetallic temperature sensors. The deformation of the cantilever measured by a Wheatstone bridge located at the clamped end changes with temperature due to the different thermal expansion coefficients of silicon and silicon dioxide. Both the bridge and the cantilever are of the same thickness and are fabricated simultaneously with the same materials and by an identical process flow. So there are few errors caused by the temperature difference between the temperature sensor and the resonator itself, which occurs during fast temperature changes.

Condensation of isolated metal clusters studied with a calorimeter

We describe the combination of molecular beam techniques with a calorimeter in order to investigate thermal properties of isolated metal clusters. A size distribution of neutral SnN clusters with 6⩽N⩽600 is deposited on a bimetallic micromechanical sensor and the released heat during the cluster deposition can be determined from the time-dependent bending of the sensor. The size distribution of the deposited clusters coming from the pulsed source has been probed with a quasicontinuous time-of-flight mass spectrometer. The formation enthalpy per atom of the investigated SnN cluster size distribution is obtained from the measured calorimetric heat to Δhf,298=0.45–0.53 eV.

Principles and methods of temperature measurement

The Concept of Temperature. The Thermodynamic Temperature Scale. Entropy, Temperature, and Statistical Mechanics. The International Practical Temperature Scale. General Characteristics of Temperature Measuring Devices and Treatment of Data. Liquid--in--Glass Thermometers. Sealed Liquid or Gas Sensing Instruments and Bimetallic Sensors. Electrical Resistance Temperature Measurement Using Metallic Sensors. Thermistors and Semiconductors for Temperature Measurement. Thermoelectric Temperature Measurement. Theory of Radiant Heat Transfer as a Basis for Temperature Measurement by Radiant Techniques. The Disappearing Filament Optical Pyrometer. Photoelectric Optical Pyrometers (Automatic and Infrared). Total Radiation Pyrometers. Novel Methods of Temperature Measurement. Pyrometric Cones. Calibration Methods. Installation Effects. Dynamic Response of Sensors. Temperature Instrumentation and Control.