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The simple sol-gel technique was utilized to prepare pure nanocomposite TiO2 and Ag\TiO2. The structure, surface as well as optic features of the pure nanocomposite TiO2 and Ag\TiO2 were verified by adding different concentrations of Ag to TiO2 at (0, 2, 4, and 6 mol%), respectively and annealed at temperatures of 450oC for 2h. The XRD diffraction patterns show anatase stage within pure TiO2, while in state of Ag\TiO2 nanocomposite there is a stage for Ag cubic corresponding to high concentrations of Ag content. The optical properties reveal the absorption band induced by surface plasmon resonance (SPR) in the visible area, which is the hallmark of Ag Nanoparticles. The FTIR analysis confirms the formation functional groups due to the interaction of TiO2 with Ag species. The surface morphology of pure TiO2 and Ag\TiO2 nanocomposite powder was distinguished through FESEM (field emitting scan electron microscopy). In state of higher Ag content, the Ag\TiO2 nanocomposite is formed with less aggregation and smaller size compared with pure TiO2.

The study effect Graphene on optical and electrical properties of glass prepared on glass substrates using sol–gel dip-coating technique. The deposited film of about (60-100±5%) nm thick. Optical and electrical properties of the films were studied under different preparation conditions, such as graphene concentration of 2, 4, 6 and 8 wt%. The results show that the optical band gap for glass-graphene films decreasing after adding the graphene. Calculated optical constants, such as transmittance, extinction coefficient are changing after adding graphene. The structural morphology and composition of elements for the samples have been demonstrated using SEM and EDX. The electrical properties of films include DC electrical conductivity; we found an increasing in current as graphene concentration increases.

This work is concerned with the preparation of alumina porous ceramic, the effect of binder (corn starch) and sintered on the physical and mechanical properties of ceramic bodies were. In this work porous raw material ceramic have been produced by using natural additive (corn starch) with (0, 5, 10, 15) wt%. The mixture were dried at 80oC for 2 hours. These samples were sintered at 10000C. Many mechanical properties tests were used to determine the properties of prepared ceramic material which involves: the linear shrinkage, water absorption, apparent porosity, diametrical compression strength, scanning electron microscope (SEM) and x-ray diffraction (X-RD). The results show the interconnected pores between (10-25µm) without additive, (15-28µm) at 5wt%, (17-35µm) at 10wt% and (20-55µm) at 15wt%. The pore size are illustrated by small and large spherical shape the corn starch particle, which are connected and contain an interconnected pores throughout small pores channels.

A theoretical investigation of the secondary ionization coefficients that responsible for the ionization current growth in uniform electric field studied. Nitrogen gas was from the range of E/p various 60 to 392 V/cm Torr, which corresponding to low values of pressures (0.05 < p < 0.684 Torr). The secondary ionization coefficients have been calculated using the breakdown criterion condition for a discharge gap in a uniform electric field. Using theoretical values of the primary ionization coefficient determined from numerically solving Boltzmann equation together with the values of the sparking distance (ds) obtained from present work. The program provided all cross-sections data from nitrogen. Experimentally, the measurement of breakdown voltage was taken after fixing sparking distance at ds= 69 cm. The results of the present work showed that, the value of breakdown voltage decreased during the increase of the secondary ionization coefficient value. Furthermore, under very low-pressure range, and within the studied sparking distance ds, the value of secondary ionization coefficient was negligible. During pressure increase, the value of secondary ionization coefficient becomes a saturation value.

Nano-crystalline SnO2 films were deposited on glass substrates using dip coating by sol–gel technique for gas sensor applications. These films have been annealed in air at 300, 350 400, and 450 °C for 60 min, and at 400 °C for 15, 30 min. The films have been analyzed through x-ray diffraction and optical absorption spectroscopy. The deposited films have shown tetragonal rutile structures. The average crystallite size increased as annealing temperature increased. The crystallite sizes of the annealed films were 8 nm at 300 °C, 10 nm at 350 °C, 14 nm at 400 °C, and 22 nm at 450 °C for 60 min. Whereas the crystallite sizes showed 16 and 15 nm at annealing temperature of 400 °C for 15 and 30 min, respectively. The energetic values of optical band gaps of the films showed increment with the elevation in annealing temperatures. The optical band gap energies were 2.86, 2.86, 3.14 and 3.35 eV at annealing temperatures of 300, 350, 400, and 450 °C, for 60 min, respectively, and 3.43 and 3.35 eV at annealing temperature of 400 °C for 15 and 30 min, respectively. Electrical D.C. conductivity were measured at temperatures ranging from 30 °C to 170 °C, and these measurements showed an exponential increment as the temperature and time increased. The films were studied in the matter of sensing capabilities for CO gas through evaluation at various times and temperatures. The optimum sensitivity was found at annealing temperature 400 °C. The outcomes revealed a high sensitivity of the deposited films for carbon monoxide at operation temperature of 200 °C.

Incredible progress in the efficiency of hybrid perovskite solar cells (PSCs) has nominated perovskites as a promising light-harvesting for new-generation photovoltaic devices. Additive engineering in PSCs is a valid and straightforward method to increase the surface quality of perovskite films. Herein, we prepared mixed cation of cesium (Cs)/formamidinium (FA)/methylammonium (MA) PSCs via an air-processed sequential deposition method. Acetonitrile (ACN) was used as an effective additive to improve the surface properties of perovskite layer. Our measurements demonstrated that with the incorporation of ACN in the FAI/MABr/MACl precursor surface defects on the perovskite film well passivated, and consequently, crystal grain size increased. A PCE of 15.64% was achieved for ACN-based PSCs higher than of 13.06% one for without additive devices. Additionally, ACN-containing devices showed a lower hysteresis effect as compared to the control devices. Most importantly, ACN additive based PSCs showed more stable behavior in ambient air, thermal, and humidity stability tests. This work introduces a simple approach for the fabrication of high-performance perovskite materials in ambient air.