The V2O5 nanoparticles were synthesized from VCl3 precursor via a rather facile sol-gel route in gelatin medium followed by calcination at different temperatures of 400, 500 and 600 °C. The prepared samples were studied for their structural, morphological, optical and magnetic properties. The results showed that the synthesized particles consist mainly of crystalline α-V2O5 orthorombic phase. The calcination at higher temperatures caused an increment in the amount of other vanadium oxides minor phases, namely β-V2O5, and also increased the crystallite size from about 22 to 29 nm. The lattice contraction observed on calcination at higher temperatures may be associated to the the lower density of oxygen vacancies. The optical studies revealed the effect of raising the calcination temperature as an red shift in their direct band gap energy from 2.92 to 2.77 eV due to the size effects. The magnetic characterization of the sample calcined at 400 °C demonstrated a weak ferromagnetic behavior with saturation magnetization of about 0.14 emu/g induced probably by the oxygen vacancies.

In this work, the Ni1-xCuxTiO3 (0 ≤x ≤ 0.1) ilmenite materials were successfully synthesized using the citrate-gel method using nickel nitrate, copper nitrate and titanium (IV) isopropoxide as Ni, Cu, Ti sources and citric acid as complexing reagent. The evolution of the microstructural properties was investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Powder X-ray diffraction pattern confirms the formation of the ilmenite phase for all the samples. The particle size of the prepared samples substantially increased with increase of copper dopant content. The study of phonon vibration by Raman spectroscopy identified a change in structure of NiTiO3 due to Cu dopant. The optical properties with the Cu content was carried out using UV-vis absorption spectroscopy. The reduction of optical band gap from 2.31 eV to 1.99 eV was obtained for undoped NiTiO3 and 10 mol.% Cu dopant in NiTiO3, respectively. To evaluate the photocatalyst properties of NiTiO3, the photocatalytic degradation of congo red under visible light irradiation was carried out. Our results revealed that the copper dopant into NiTiO3 lattice promoted the increase of particle size, decrease of optical bandgap and enhancement of textile photodegradation.

In the present work, the zinc oxide nanoparticle and its composite have prepared with the graphene as a photoanode electrode as well as synthesizing an excellent thin film from the PEDOT: PSS, which is conductive polymer loading with MWCNT as an auxiliary electrode for the DSSC. The photoanode characterized using ( XRD, FTIR, Raman spectroscopy, BET-BJH, and UV-DRS). The FESEM and AFM performed to study morphology and structure of ZnO, ZnO/Graphene, and PEDOT: PSS/MWCNT thin films. The results confirm a successful fabrication of the thin films on the ITO by using the electrophoretic deposition method as well the added of graphene reduced the band gap close to 3.0eV. Moreover, the PEDOT: PSS/MWCNT nanocomposite based an auxiliary electrode offered high electrical conductivity, which enhanced the photovoltaic values of DSSC. The BET-BJH results demonstrated of the synthesis of zinc oxide nanoparticles at the surface area 6.66 m2/g and pore size 1.42 m3/g.

In this paper the electrical characteristics of a nano scale silicon gate-all-around field effect transistor (GAA-FET) with different dielectrics in the gate electrode are predicted. For this, we first calibrate physics based TCAD simulator against experimental results reported by IBM. Then the device electrical figures of merit comprised of ION/IOFF, transconductance (gm) and subthreshold slope (SS) are extracted. The obtained results show that utilizing various high-k gate dielectrics has a noticeable impact on the device performance. Different high-k gate dielectrics comprised of Al2O3, Si3N4 and HfO2 are explored in our study. Moreover, when high-k gate dielectric is used instead of conventional SiO2 insulator, the electrical characteristics will be improved in terms of ION/IOFF ratio, transconductance to drive current ratio (gm/IDS) and SS. Based on our simulations and obtained results, scaling GAA-FETs by utilizing high-k dielectrics offers superior electronic devices and promising candidates for “more Moore” domain and integrated circuit applications.

In this study, the chemical bath deposition (CBD) strategy was applied for preparation of pure and Lithium-doped copper sulfide (CuS) thin film on glass. The CuCl2.2H2O, as a copper source and thiourea as a sulfur source were used. The structural, topographical, and optical properties of products were characterized via powder X-ray diffraction (XRD), atomic force microscopy (AFM), and UV-Vis spectroscopy. Results showed that the crystalline size is increased via Lithium doping, though the strain (%) parameter decrease from 30.39 to 27.47. Obtained results revealed that doing of lithium has a significant effect on the optical properties of prepared CuS-based thin films. The optical properties of samples was investigated through band gap calculation. The bands gap were calculated 2.4, 2.5, and 2.6 eV for CuS:3% Li, CuS:1% Li and pure CuS thin films respectively. Based on attractive properties of prepared thin films, Lithium-doped CuS thin film has potential application in optoelectronic fields.

Ferrite chromite (FeCr2O4) powders have been synthesized by a hydrothermal method using various alkaline agents and capping agent. For the first time, nanostructured Ferrite chromite was synthesized with utilizing tetraethylenepantamine as a new alkaline agent. The SDS, PVP and PEG as stabilization agent and capping agent in presence of TEPA as alkaline agent were employed to prepare of the Ferrite chromite. The structural character of as-synthesized powders was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray microanalysis (EDX). The results indicate that the as-obtained powders are pure. The electronic properties of as-synthesized powders was characterized by UV–Vis diffuse reflectance analysis (DRS), which shows the as-obtained sample has a significant absorption in the UV region. The photocatalytic degradation of the rhodamine B, methyl orange, murexide and methylene blue as water pollutants were investigated. According to the results, photocatalytic activity of FeCr2O4/Ag nanostructures were better than of other samples and degradation percent of rhodamine B as a cationic pollutant was more than the other dyes.

Fe3O4 magnetic structure was synthesized with co-precipitation method. Surface of magnetic core was modified with hydrophobic BMIM[PF6] ionic liquid. The samples became antibacterial by loading gold, copper and silver nanoparticles and denoted as Fe3O4/IL/X (X=Ag, Au, Cu). X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), thermal gravimetric analysis (TGA), Atomic absorption spectroscopy (AAS), Fourier transform infrared (FTIR) and vibration sample magnetometer (VSM) technics were applied for catalysts characterization, metal concentration analysis and morphology monitoring. Modified nanostructures were used for inactivation of Escherichia coli as the gram negative and Staphylococcus aureus as the gram positive of bacteria. Transmition electron micrscopy (TEM) images indicated that highest bacteria cell walls destruction is achieved when the surface of the magnetic nanostructure is coated with gold particles. Hydrogen bonds between cell wall and ionic liquid and gradual release of metals from Fe3O4/IL surface facilitate the metals arrive to outer layer of bacteria. Minimum inhibitory concentration (MIC) study approved the positive effect of ionic liquid.

Nanofibers are one of the most widely used materials in various industrial sectors. Among them Titanium Dioxide (TiO2) nanofibers are excelled, moreover they are environmentally friendly and have shown that they have diverse industrial applications. The physical structure of this fiber (diameter and surface characteristics) is a key effective factor on its behavior for corresponding applications. In this study, the effects of different factors influencing the diameter of TiO2 nanofibers were analyzed and quantified using two statistical analyses namely the Response Level Method (RSM) and the Composite Central Design (CCD) method. The preparation parameters of polymer synthesis including the electrical potential, the distance between electrodes tips, flow rate, and ambient humidity were studied. Results marked polymer concentration as the most important factor affecting the diameter of the nanofibers. However the diameter was almost independent from flow rate, and hence marked as the least effective factor. Furthermore, as humidity increased, the diameter of the fibers decreased significantly and surface roughness increased as demonstrated in the SEM and FESEM images. Since the relative humidity has intense impact on the structural properties of titanium dioxide nanofibers, humidity condition of synthesis space must be strictly controlled and kept below a threshold (38%).

A new nanomaterial based on folic acid functionalized dendritic fibrous nano-silica (FA-KCC-1-NH2) was synthesized and used as a recyclable solid acid and heterogeneous nanocatalyst towards efficient amidation of a variety of carboxylic acids with amines in toluene under reflux conditions. KCC-1 porous nanomaterials were produced utilizing a hydrothermal technique and in the next functionalized with folic acid moieties to yield KCC-1-NH-FA nanocatalyst. The structure of KCC-1, KCC-1-NH2 and KCC-1-NH-FA nanoparticles were investigated by FESEM, DLS, zeta potential and TEM, instrumental techniques. Also, the pore size of KCC-1-NH-FA nanoparticles were moreover investigated with BET where results revealed that the surface of this nanocomposite was expanded. The synthesized KCC-1-NH-FA nanoparticles showed effective catalytic activity in amidation of carboxylic acids with amines affording in high yields (76-89%) and short period of times. Moreover, other advantages of present method are easy workup, no need to use of chromatographic column and excellent recyclability of catalyst without significant loss in its catalytic activity which gives economic rewards.

In this work, a novel Silicon on Insulator (SOI) MOSFET is proposed and investigated. The drain and source electrode structures are optimized to enhance ON-current while global device temperature and hot carrier injection are decreased. In addition, to create an effective heat passage from channel to outside of the device, a silicon region has embedded in the buried oxide. In order to reduce the device leakage current and controlling the threshold voltage, a p-type retrograde doping is introduced into channel region. Since the air has the least permittivity among materials, it can be utilized to decrease the device parasitic capacitances. Based on this, an air gap is embedded in the buried oxide near the silicon to improve RF performance of the device. Because the source and drain electrodes are embedded in and over the silicon film in the source and drain regions, we called this structure EEIOS-SOI MOSFET. “EEIOS” stands for “Embedded Electrodes In and Over the Silicon film”. During this work, EEIOS-SOI MOSFET is compared with a conventional SOI MOSFET and another SOI MOSFET with just Embedded Electrodes In the Silicon Film (EEIS-SOI). EEIS-SOI presents better electrical figure of merits including lower subthreshold slope and lower leakage current in simulations. An immense investigation among these devices shows that EEIOS-SOI MOSFET has better transconductance, lower gate injection leakage current and lower temperature related to DC parameters and higher cut off frequency, gain bandwidth product and unilateral power gain related to AC figures of merits compared to its counterparts.