Photodetector based on Rutile and Anatase TiO2 nanostructures/n-Si Heterojunction

Rutile and anatase titanium dioxide TiO2 nanostructures has been prepared successfully by hydrothermal technique. Also Rutile and anatase TiO2/n-Si heterojunction detector (HJ) has been fabricated. Hall Effect measurements confirmed that prepared films are n-type. The optical absorption spectra showed the prepared films have peak absorption in UV region. TiO2/n-Si heterojunction had exhibited diode-like rectifying I-V behaviour in the dark as well as under the illumination. Ideality factor greater than 2 and rectification factor for Rutile TiO2/n-Si HJ is equal 32.0961 higher than anatase TiO2/n-Si HJ. Photodetetor based on rutile TiO2/n-Si HJ showed higher responsivity and incident photon-to-current efficiency (IPCE) than photodetector based on anatase TiO2/n-Si HJ. Photodetetor based on rutile TiO2/n-Si HJ has responsivity is 69.11Amp/W at 570 nm and IPCE is 21.2%at 370nm and 1.38% at 570nm. For the purpose of investigating the impacts of TiO2 crystal phase upon the performance of the device despite the fact that rutile has a lower band gap compared to anatase, rutile exhibits better photovoltaic activity due to its higher specific surface area.

Social Learning Class Topper Optimization (SL-CTO) Based Hop Localization Technique for Wireless Sensor Network

To address the current situation limitation of traditional DV-Hop, we suggested a DV-Hop localization based on a rectification factor using the Social Learning Class Topper Optimization (SL - CTO) algorithm in that paper. In order to adjust the number of hops between beacon nodes, we have implemented a rectification factor in the suggested method. By measuring the dimensions of all the beacons at dumb nodes, the suggested algorithm decreases communication among unknown or dumb and beacon nodes. The model of network imbalance, It is often considered to be demonstrate a applicability of the Proposed approach in the anisotropic network. Simulations have been performed on LabVIEW@2015, and Comparisons were made with conventional DV-Hop, particle swarm optimization-based DV-Hop and runner-root optimization-based DV-Hop for our proposed algorithm. In comparison to current localization methods, simulation outcomes showed that the proposed localization technique reduces computing time, localization error variance and localization error.

Heterogeneous irradiated-pristine polyethylene nanofiber junction as a high-performance solid-state thermal diode

In this work, we demonstrate two types of heterogeneous irradiated-pristine polyethylene nanofiber junctions, ‘heavily-irradiated-pristine’ (HI-P) and ‘lightly-irradiated-pristine’ (LI-P) junctions, as high-performance solid-state thermal diodes. The HI-P junction rectifies heat flux in a single direction, while the LI-P junction shows dual-directional rectification under different working temperatures. We accurately model the phase transition of polyethylene nanofibers with a finite temperature range rather than a step function. The finite-temperature-range model suggests that the rectification factor increases with temperature bias and there is a minimum threshold of temperature bias for notable rectification. Besides, the finite-temperature-range model shows better prediction for the heat flow data from experiments, while the step function model tends to overestimate the rectification performance around the optimal length fraction of irradiation. Although both the models show that an optimal rectification occurs when the interface temperatures in the forward and the reverse biases are equal, the optimized rectification factor is determined by the temperature bias and the temperature range of phase transition. This work elucidates the influence of both the temperature bias and the temperature range of phase transition on thermal rectification performance, which could incredibly benefit the evaluation and design of thermal diodes.

Electrical Characterization of Si/ZnO Nanorod PN Heterojunction Diode

The electrical characterization of p-Silicon (Si) and n-Zinc oxide (ZnO) nanorod heterojunction diode has been performed. ZnO nanorods were grown on p-Silicon substrate by the aqueous chemical growth (ACG) method. The SEM image revealed high density, vertically aligned hexagonal ZnO nanorods with an average height of about 1.2 μm. Electrical characterization of n-ZnO nanorods/p-Si heterojunction diode was done by current-voltage (I-V), capacitance-voltage (C-V), and conductance-voltage (G-V) measurements at room temperature. The heterojunction exhibited good electrical characteristics with diode-like rectifying behaviour with an ideality factor of 2.7, rectification factor of 52, and barrier height of 0.7 V. Energy band (EB) structure has been studied to investigate the factors responsible for small rectification factor. In order to investigate nonidealities, series resistance and distribution of interface state density (NSS) below the conduction band (CB) were extracted with the help of I-V and C-V and G-V measurements. The series resistances were found to be 0.70, 0.73, and 0.75 KΩ, and density distribution interface states from 8.38 × 1012 to 5.83 × 1011 eV−1 cm−2 were obtained from 0.01 eV to 0.55 eV below the conduction band.

FABRICATION AND CHARACTERIZATION OF TiO2 THIN FILM FOR DEVICE APPLICATIONS

Titanium oxide (TiO2) film was deposited by rectification factor (RF) magnetron sputtering technique on glass substrates and p-Si (111) wafers to fabricate n-TiO2/p-Si heterojunction devices for the investigation of material and device properties, respectively. The structural, surface morphology, optical and electrical properties of TiO2 film were characterized by means of scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), UV–visual (UV–Vis) spectral and dark current-voltage (I–V) measurement analyses. The deposited film layer was found to be homogeneous structure with crack-free surface. The bandgap value of TiO2 film was determined as 3.6[Formula: see text]eV and transmission was around 65–85% in the spectral range of 320–1100[Formula: see text]nm. The conductivity type of the deposited film was determined as n-type by hot probe method. These values make TiO2 film a suitable candidate as the n-type window layer in possible diode applications. TiO2 film was also deposited on p-Si (111) wafer to obtain Al/n-TiO2/p-Si/Al heterojunction device structure. The dark I–V characteristic was studied to determine the possible conduction mechanisms and diode parameters.

Electronic Behaviour of Schottky Diodes Fabricated from Electroplated CdSe Semiconductors

The fabrication of Schottky diodes using electroplated n- type CdSe thin films and gold metal contact have been successfully achieved. The electronic properties of the fabricated diodes with the device structure glass/FTO/n-CdSe/Au have been investigated by current-voltage (I-V) and capacitance-voltage (CV) measurement techniques. The I-V characteristics revealed a good rectifying behaviour with an ideality factor of 1.50, a potential barrier height (ϕb) >0.79 eV and rectification factor (RF) surpassing 102 at 1.0 V. Results from the C-V measurement showed that the fabricated Schottky diodes have doping density of ~1.61 × 1017 cm-3 and a built-in potential (Vbi) of 0.24 V which falls in the range of reported Vbi values for Schottky diodes. Both I-V and C-V parameters revealed that the CdSe Schottky diodes possess qualities for excellent performance in electronics circuit or as an electronic device.

RESEARCH OF MINERAL ADSORBENTS APPLICATION FOR WATER-ALCOHOL SOLUTIONS PURIFICATION IN TECHNOLOGY OF ALCOHOLIC BEVERAGES

The possibility of using natural mineral adsorbents - clinoptilolite and schungite - in the adsorption purification of water-alcohol solutions of different concentrations was studied using the example of impurities of ethanol of acetaldehyde and ethyl acetate. The feasibility of studying the above-mentioned minerals for the adsorption of simple organic substances is justified. The best concentration of a water-alcohol solution for adsorption of acetaldehyde 80-85 vol.%, ethyl acetate-40 vol.% is experimentally established. The rational duration of phase contact for adsorption of acetaldehyde is from 10 to 20 minutes, for adsorption of ethyl acetate - 5 minutes. An explanation for the dependence of the sorption efficiency on the ethanol content in a water-alcohol solution is proposed based on the known dependencies of the rectification factor on the ethanol concentration. The larger the rectification factor, the less the hydrogen bond of this impurity with ethanol and the easier it is to sorb it from ethanol by mineral adsorbents. The practical and economic feasibility of using the mineral adsorbent clinoptilolite of Ukrainian origin in the preparation of alcoholic beverages instead of imported active coal is shown. It is determined that to purify water-alcohol solutions from aldehydes, which most worsen the taste of alcoholic beverages, it is more expedient to use clinoptilolite as an adsorbent. It is shown that the use of clinoptilolite for the preparation of vodkas from non-standard rectified alcohol will improve the tasting indicators of the final product.

A concentration-independent micro/nanofluidic active diode using an asymmetric ion concentration polarization layer

The new class of micro/nanofluidic diodes with an ideal perm-selective membrane were demonstrated at a wide concentration range from 10−5 M to 3 M. Moreover, the rectification factor was actively controlled by adjusting the external convective flows.

Metal–insulator–semiconductor field-effect transistors (MISFETs) using p-type SnS and nanometer-thick Al2S3 layers

SnS based MISFET devices exhibit a high turn-on voltage of +5.13 V and rectification factor of 1383@+6 V.