ZnO nanostructures of different methods and sizes were grown in a controlled manner using a simple hydrothermal and sonochemical technique. Controlling the content of concentration and temperature of the reaction mixture, spherical nanoparticles ZnO structures could be synthesized at temperatures 100-150 °C with excellent reproducibility in solvothermal and at different power and time in sonoch...

Sensing of gases is a promising area for applications of photonic systems operating in the mid-infrared spectral range. We present an infrared evanescent-field absorption gas sensor based on a silicon strip waveguide, which was specifically designed for CO2 sensing. We discuss finite element simulations that were used to design the strip waveguide and furthermore present experimental data of qu...

A 440MHz wireless and passive Love-wave-based chemical sensor was developed for CO2 detection. The developed device was composed of a reflective delay line patterned on 41 YX LiNbO3 piezoelectric substrate, a poly(methyl methacrylate) (PMMA) waveguide layer, and Teflon AF 2400 sensitive film. A theoretical model is presented to describe wave propagation in Love wave devices with large piezoelec...

A potentiometric sensor device based on screen-printed Nasicon films was investigated. In order to transfer the promising sensor concept of an open sodium titanate reference to thick film technology, "sodium-rich" and "sodium-poor" formulations were compared. While the "sodium-rich" composition was found to react with the ion conducting Nasicon during thermal treatment, the "sodium-poor" refere...

Transferable ZnO tetrapods were grown by an aqueous solution method. An individual ZnO tetrapod-based sensor was fabricated by in situ lift-out technique and its ultraviolet (UV) and gas sensing properties were investigated. This single tetrapod-based device responds to the UV light rapidly and showed a recovery time of about 23 s. The sensitivity of a single ZnO tetrapod sensor to oxygen conce...

Laser-based atmospheric trace-gas sensors have great potential for long-term, real-time, maintenance free environmental monitoring in distributed Wireless Sensor Networks (WSN). We are developing a laser based chemical sensing technology with wide-area autonomous wireless sensor networking as the final target. Our prototype sensor measures atmospheric oxygen concentration in the form of a batte...

The parts-per-billion-level nitric oxide (NO) gas sensing capability of a copper-ion-doped polyaniline/tungsten oxide nanocomposite (Cu(2+)/PANI/WO3) film coated on a Rayleigh surface acoustic wave device was investigated. The sensor developed in this study was sensitive to NO gas at room temperature in dry nitrogen. The surface morphology, dopant distribution, and electric properties were char...

gas sensitive metal oxide layers used in fabrication of resistive gas sensors are prepared by different deposition techniques. the technical data reported on some basic and practically important specifications of these devices, although fabricated based on the same gas sensitive oxide, are anomalously different. the influence of the fabrication technique used for the deposition of the gas sensi...

The increase in CO2 gas occurred very significantly due to the use of fossil fuels, industry, forest fires, volcanic eruptions and natural resulting air pollution. dangers CO? for humans can cause headaches, sweating, blurred vision, tremors, loss consciousness after exposure five ten minutes. is a poisonous which physically colorless odorless. This characteristic causes many be unaware existen...