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The purpose of this paper is to study the effect of doping, annealing temperature and visible optical excitation on CuO-ZnO nanocomposites’ acetone sensing properties and introduce an attractive candidate for acetone detection at about room temperature.

ZnO nanoparticles doped with CuO were prepared by sol-gel method, and the structure and morphology were characterized via X-ray diffraction, scanning electron microscope, energy dispersive spectroscopy and Brunauer-Emmett-Teller. The photoelectric responses of CuO-ZnO nanocomposites to cetone under the irradiation of visible light were investigated at about 30°C. The photoelectric response mechanism was also discussed with the model of double Schottky.

The doping of CuO enhanced performance of ZnO nanoparticles in terms of the photoelectric responses and the gas response and selectivity to acetone of ZnO nanoparticles, in addition, decreasing the operating temperature to about 30ºC. The optimum performance was obtained by 4.17% CuO-ZnO nanocomposites. Even at the operating temperature, about 30ºC, the response to 1,000 ppm acetone was significantly increased to 579.24 under the visible light irradiation.

The sensor fabricated by 4.17% CuO-ZnO nanocomposites exhibited excellent acetone-sensing characteristics at about 30ºC. It is promising to be applied in low power and miniature acetone gas sensors.

In the present research, a new nanocomposite material of CuO-ZnO was prepared by Sol-gel method. The optimum gas sensing properties to acetone were obtained by 4.17% CuO-ZnO nanocomposites at about 30ºC operating temperature when it was irradiated by visible light with the wavelength more than 420 nm.

This study aims to investigate photosensing characteristics of SiC and GaN nanowire-based devices through exposure to UV light. The photocurrent transients have been modeled to determine rise and decay process time constants. The 1D-semiconductor nanowires can exhibit higher light sensitivity compared to bulk materials because of their large surface area to volume ratio and the quantum size effects.

Nanowire devices have been fabricated through dielectrophoresis for integrating nanowires onto pre-patterned electrodes (10 nm Ti/ 90 nm Au) with a spacing about 3 µm onto SiO₂/Si (doped) substrate. The photocurrent measurements were carried out under room temperature conditions with UV light of 254 nm wavelength.

SiCNWs yield very short rise and decay time constants of 1.3 and 2.35 s, respectively. This fast response indicates an enhanced surface recombination of photoexcited electron-hole pairs. Conversely, GaNNWs yield longer rise and decay time constants of 10.3 and 15.4 s, respectively. This persistent photocurrent suggests a reduced surface recombination process for the GaNNWs.

High selective UV light sensitivity, small size, very short response time, low power consumption and high efficiency are the most important features of nanowire-based devices for new and superior applications in photodetectors, photovoltaics, optical switches, image sensors and biological and chemical sensing.

The purpose of this paper is to study the electronic transport performance of Ag-ZnO film under dark and UV light conditions.

Ag-doped ZnO thin films were prepared on fluorine thin oxide (FTO) substrates by sol-gel method. The crystal structure of ZnO and Ag-ZnO powders was tested by X-ray diffraction with Cu Kα radiation. The absorption spectra of ZnO and Ag-ZnO films were recorded by a UV–visible spectrophotometer. The micro electrical transport performance of Ag-ZnO thin films in dark and light state was investigated by photoassisted conductive atomic force microscope (PC-AFM).

The results show that the dark reverse current of Ag-ZnO films does not increase, but the reverse current increases significantly under illumination, indicating that the response of Ag-ZnO films to light is greatly improved, owing to the formation of Ohmic contact.

To the best of the author’s knowledge, the micro electrical transport performance of Ag-ZnO thin films in dark and light state was firstly investigated by PC-AFM.

The purpose of this paper is to investigate the optoelectronic properties of the multichannel ZnO UV photodetectors.

ZnO nanowires were assembled by dielectrophoresis for the UV photodetectors. Different ZnO channels were adjusted by different alternating current voltages and investigated for UV optoelectronic properties.

The number of the ZnO channels increases with the enhancing alternating current voltage. Optimum performance of the UV photodetectors is obtained with more channels.

Dielectrophoresis is a promising method for controllable assembly of multichannel ZnO photodetectors. ZnO photodetectors with more channels demonstrate a good response to 380-nm UV light, which shows great potential application in UV photodetector.

Multiple-source disturbances exist in the polarization sensor, which severely affect the sensor accuracy and stability. Hence, the disturbance analysis plays a vital role in improving the sensor orientation performance. This paper aims to present a novel sensor error model, a disturbances quantitative analysis, a calibration and performance test of polarization sensor based on a polarizing beam splitter.

By combining with the sensor coefficient errors, the Azimuth of Polarization (AoP) error model and the Degree of Polarization (DoP) error model are established, respectively. In addition, the multiple-source disturbances are classified, while the influence on the orientation accuracy is quantitative analyzed. Moreover, the least square optimization algorithm is employed to calibrate the sensor coefficients. Finally, an outdoor test is carried out to test the sensor long-term accuracy.

The theoretical analysis and numerical simulations illustrate that the sensor accuracy is closely related to the disturbances. To eliminate the influence of the disturbances, the least square optimization algorithm, which can minimize the sum of squares of the residual difference of AoP and DoP, is used to calibrate the sensor coefficients. The outdoor test indicates that the sensor can maintain long-term accuracy and stability.

The main contribution of this paper is to establish a novel sensor error model, where the sensor coefficient errors are introduced. In addition, the disturbances are classified and analyzed to evaluate the orientation accuracy of the sensor.

The aim of this paper is to synthesize graphene-modified titanium dioxide (GR-TiO₂) nanorod arrays nanocomposite films, so that these can enhance the photocatalytic properties of titanium dioxide and overcome the problem of difficult separation and recovery of photocatalysts.

The GR-TiO₂ nanocomposite films were synthesized via hydrothermal method and spin-coating. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet–visible (UV-Vis) diffuse reflectance spectrum and Raman spectrum. The photocatalytic performance of the GR-TiO₂ nanocomposite films for degrading Rhodamin B under ultraviolet (UV) was studied by a UV-Vis spectrophotometer. The photocatalytic enhancement mechanism of graphene was studied by photoelectrochemical analysis.

The introduction of graphene expanded the range of the optical response of TiO₂ nanorod arrays, improving the separation efficiency of the photogenerated electron-hole pairs, and thus dramatically increasing its photocatalytic performance.

A simple and novel way for synthesizing GR-TiO₂ nanocomposite films has enhanced the photocatalytic performance of TiO₂.

The photocatalyst synthesized is easy to separate and recycle in the process of photocatalytic reaction, so it is possible to achieve industrialization.

The purpose of this study is to construct imaging pixels using novel bioactive films. Despite the notable progress in electronic imaging devices, these sensors still cannot compete with biological vision counterparts such as the human eye. Light sensitive biolayers and pigments in living organisms show superior performance in terms of low noise operation and speed. Although photoactive biolayers have been used to construct electronic imaging devices, they are usually hard to develop, and the organisms that produce these active layers have low growth rates.

Among 40 pigment producing prokaryotic marine bacteria, four strains which show faster growth rates in the presence of light are screened and characterized by Fourier transform infrared spectroscopy and visible absorption. Subsequently, they are used as active layers in light sensitive sensors. The performance of the obtained cells is eventually evaluated by time domain photoresponse measurements.

It is shown that while the obtained strains have high growth rates and their mass volume reproduction is relatively simple, they provide many interesting characteristics such as high speed and low noise operation when incorporated as photosensitive layers.

Because the mass reproduction of the obtained cultures is simple, they are an appropriate choice for use in planner and flexible document imaging devices and DNA microarray sensors.

The purpose of this paper is to improve photoelectric detection target (PDT) optical detection performance and detection view, by analyzing its influence factors and putting forward a new method to design its optical detection system.

Using rectangle linked photoelectric detector, with low noise and high response, to design optical detection system and gain faint projectile image information; bringing forward a deviating focusing technique to eliminate detection blind area of photoelectric detector; and designing adjustable slit diaphragm to weaken background light influence.

The results of experimentation in shooting range show that the new PDT has improved detection sensitivity and performance.

The paper presents a new design method in photoelectric detection target (PDT) optical detection system, which can provide a new method to design fire across measurement system and gain accurate projectile's coordinates data in the shooting range.

The purpose of this paper is to evaluate the detection performance of infrared photoelectric detection system and establish stable tracking platform.

This paper puts forward making use of the finite element analysis method to set up the infrared radiation characteristics calculation model of flying target in infrared photoelectric detection system; researches the target optical characteristics based on the target imaging detection theory; sets up the heat balance equation of target’s surface node and gives the calculation method of total radiation intensity of flying target; and deduces the target detection distance calculation function; studies the changed regulation of radiation energy that charge coupled device (CCD) gain comes from target surface infrared heat radiations under different sky background luminance and different target flight attitude.

Through calculation and experiment analysis, the results show that when the target’s surface area increases or the target flight velocity is higher, the radiation energy that CCD obtained is higher, which is advantageous to the target stable detection in infrared photoelectric detection system.

This paper uses the finite element analysis method to set up the infrared radiation characteristics calculation model of flying target and give the calculation and experiment results; those results can provide some data and improve the design method of infrared photoelectric detection system, and it is of value.

Vibration measurement is needed in many industrial production processes, such as equipment monitoring, fault diagnosis, and noise analysis and eliminating and so on. The purpose of this paper is to propose a simple vibration testing system which includes the laser, the string, position sensitive detector (PSD) and the corresponding signal processing circuit.

PSD is an optical semiconductor sensor that can fast locate the luminous spot position precisely, which means that it can output different electric current according to the luminous spot at different position of its surface. Moreover, the experiment on PSD sensor using different vibration source and frequency had been carried out. Finally, the vibration waveform of the luminous spot on PSD photosurface was obtained.

According to the experimental results, each kind of vibration parameter with different vibration source, such as vibration frequency and amplitude can be calculated.

The experimental results agreed with the actual parameter, which showed PSD not only had its own good qualities in the position measurement, but also had the unique superiority in the vibration measurement.