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International Conference on Photovoltaic Technologies (PVCon) -- JUL 04-06, 2018 -- Middle E Tech Univ, Culture & Convent Ctr, Ankara, Turkey, WOS: 000499762300011, In the present study, using a large area roll-to-roll DC magnetron sputtering system deposition of ITO thin films on polyethylene terephthalate (PET) substrates were achieved. In order to investigate the effect of growth conditions on the film properties all through the deposition process, optical emission spectroscopy (OES) analysis have been accomplished in a governable way. The consequences of Oxygen partial pressure and film thickness on electrical, and optical properties of the films were determined. It was shown that the intensity of optical emission peaks are subjected to the discharge power and as well as the O-2/Ar flow ratio. Large area, uniform ITO films with relatively high transparency and low electrical resistivity (R(2)(

CdSe semiconductor thin films were grown on indium tin oxide (ITO) coated glass substrates by co-electrochemical deposition method. Deposition potential was kept at - 0.95 V vs. Ag/AgCl reference electrode for ten minutes. Deposition electrolyte includes an aqueous solution of 10 mM CdCl2, 20 mM H(2)SeO(3 )as precursors, 200 mM LiCl as complexing agent, and HCl for adjusting of pH. Deposited CdSe thin film was annealed at 500 degrees C for 30 min in air medium. Precursor and annealed CdSe thin films were characterized using a number of techniques, including SEM, EDX, XRD, UV-vis spectroscopy, and electrochemical impedance spectroscopy. SEM studies show that annealing alters the surface of precursor CdSe film from smooth to granular appearance. According to EDX analyses, the ratio of Cd/Se is close to 1.07 and 1.04 for the precursor and annealed CdSe thin film, respectively. XRD analysis shows that each film has polycrystalline structure. Precursor film has only cubic structure of CdSe, while annealed film has hexagonal structure of CdSe and cubic crystal phase of CdO. Optical energy band gap of the as-deposited CdSe film increases from 1.64 to 1.71 eV after annealing due to the mixture of the two phases. Refractive index against wavelength changes between 2.0 and 3.3. Calculations performed by using the data of Mott-Schottky measurements show that precursor CdSe film has 1.72 x 10(16 )cm(-3), while annealed film is of 3.65 x 10(17 )cm(-3 )carrier concentration. The prepared films exhibit n-type semiconductor character. The study reports energy level diagrams of the produced semiconductor CdSe thin films by using the Mott-Schottky and Tauc's approximations. The carrier transport properties in the interface between active CdSe thin film and electrolyte are discussed based on an equivalent electronic circuit simulated to the Nyquist data of the CdSe/electrolyte system.

Herein, pure and cobalt (Co) doped cadmium oxide (CdO) thin films successfully deposited onto glass slides by successive ionic layer adsorption and reaction (SILAR) method. And, the structural, morphological, optical, and electrical properties were studied by employing X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), Energy dispersive X-ray analysis (EDAX), Ultraviolet-visible spectroscopy (Uv-vis), Photoluminescence (PL) spectrum, I-V measurements for the produced samples. The XRD analysis uncovered that the CdO films exhibited cubic phase of cadmium oxide with the preferred orientation (111) plane. And, it showed that Co atoms successfully incorporated into the CdO lattices as no secondary phases were detected in the XRD spectra. The FE-SEM images displayed that the introduced impurities modified the surface morphologies. The EDAX analysis definitely proved the presence of the aimed materials (Cd, O, and Co) on the SILAR grown samples. The Uv-vis spectroscopy showed that optical energy bandgap enhanced from 2.5 eV to 2.93 eV as CdO nanostructures (NSs) doped with the different Co doping concentrations. The PL spectrum revealed that the luminescence characteristics of produced films were evidently influenced by the Co doping in the CdO NSs. Also, the resistivity of the produced samples was found to be decreased by the help of the I-V measurements.

The composite of samarium doped ceria (Sm0.2Ce0.8O2-delta, SDC) and co-doped barium cerate (BaZr0.1Ce0.7Y0.1Yb0.1O3-delta, BZCYYb) is prepared by mechanical mixing and investigated as electrolyte for intermediate temperature solid oxide fuel cells (IT-SOFCs). Coexistence of SDC and BZCYYb are observed for composite electrolyte by X-ray diffraction after sintering at 1500 degrees C for 5 h, while the slight deviation of the diffraction peak indicating the element diffusion between two phases. The scanning electron microscope and electron probe microanalyzer results demonstrate that small BZCYYb grains disperse uniformly around the grains of SDC, limiting the growth of SDC grains and decreasing the average grain size of composite electrolyte. Impedance spectroscopy measurement reveals that the grain boundary resistance can be significantly reduced by about an order of magnitude through adding 15-30 wt. % BZCYYb to SDC. Single cells based on the composite electrolyte are fabricated using nickel cermet (Ni-SDC) anode and perovskite (La0.6Sr0.4Co0.2Fe0.8O3-delta, LSCF) cathode., Relatively high open circuit voltage (OCV), much lower polarization resistance and encouraging high power density are obtained for cells with composite electrolyte compared to those with single SDC electrolyte. Among all of the samples, single cell based on 15 wt. % BZCYYb-85 wt. % SDC composite electrolyte exhibits the lowest total resistances of 0.641 Omega.cm(2) and the highest peak power densities of 0.56 W. cm(-2) at 600 degrees C. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Room temperature multiferroism with enhanced ferro and piezoelectric properties of a new lead-free MnO2 added 0.90(Li0.12Na0.88NbO3)-0.10BaTiO(3) ceramic is reported. The addition of MnO2 as an additive resulted in a two fold increase in remnant polarization (P-r) (from similar to 7.30 to 17.20 mu C/cm(2)), similar to 50% increase in large-signal piezoelectric coefficient (d(33)(center dot)) (from similar to 117 to176 pm/V) and symmetric butterfly loop are observed. Phase analysis revealed that MnO2 entered the host lattice as Mn2+ and Mn4+-ions and induced room temperature ferromagnetic-like character. Interestingly, an intrinsic coupling between the two ferroic orders is evidenced by the observation of a magneto-electric voltage coefficient (etE) of similar to 0.94 mV/cm.Oe. (C) 2018 Acta Materialia Inc Published by Elsevier Ltd. All rights reserved.

The usage of the Gadolinium oxide (Gd2O3) as sensitive region in the MOS (Metal-Oxide-Semiconductor)-based dosimeters was investigated in the presented study. The Gd2O3 films grown on p-type Si (100) by RF magnetron sputtering were annealed at 800 degrees C under N-2 ambient. The back and front metal contacts were establishes to produce MOS capacitors. The fabricated Gd2O3 MOS capacitors were irradiated in the dose range 0.5-50 Gy by Co-60 gamma source. The performed Capacitance-Voltage (C-V) curves of the Gd2O3 MOS capacitors shifted to right side relative to pre-irradiation one. While continuous increments in the oxide trapped charges with increasing in gamma dose were observed, interface trapped charges fluctuated in the studied dose range. However, the variation of the interface trapped charge densities was found in the order of 10(11) cm(-2) and no significant variation was observed with applied dose. These results confirm that a significant deterioration does not occur in the capacitance during the irradiation. The higher oxide trapped charges compared to interface trapped charges showed that these traps were more responsible for the shift of the C-V curves. The sensitivity and percentage fading after 105 min of the Gd2O3 MOS capacitor were found as 39.7 +/- 1.4 mV/Gy and similar to 14.5%, respectively. The devices sensitivity was found to be higher than that of capacitors composed of Er2O3, Sm2O3, La2O3, Al2O3, and SiO2, but, the high fading values is seen as a major problem for these capacitors. Finally, the barrier height was investigated with gamma exposure and the results showed that its value increased with increasing in radiation dose due to possible presence of the acceptor-like interface states. Türkiye Cumhuriyeti Kalkınma Bakanlığı -- 2016K121110

Annealing treatment of as-deposited beta-Sn film on Cu resulted in the development of 'composite' film comprised of Sn-Cu intermetallic phases (Cu3Sn and Cu6Sn5) surrounding 'percolating' network of beta-Sn, all underneath a thin continuous beta-Sn layer. Such phase assemblage and microstructure-type resulted in significantly improved mechanical integrity upon lithiation/delithiation; and accordingly very stable Li-capacity retention with continued electrochemical cycling. In-situ monitoring of the stress developments during lithiation/delithiation indicated that the presence of intermetallic 'buffer' phase(s) results in similar to 3 times lower stress magnitudes compared to 'pure' Sn upon 'full' lithiation, along with absence of signature for mechanical degradation in the stress-time profiles. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

A novel combination of solar physical vapor deposition (SPVD) and electrophoretic deposition (EPD) that was developed to grow MgTiO3 nanostructured thick films is presented. Obtaining nanostructured MgTiO3 thick films, which can replace bulk ceramic components, a major trend in electronic industry, is the main objective of this work. The advantage of SPVD is direct synthesis of nanopowders, while EPD is simple, fast and inexpensive technique for preparing thick films. SPVD technique was developed at CNRS-PROMES Laboratory, Odeillo-Font Romeu, France, while the EPD was performed at University of Aveiro DeMAC/CICECO, Portugal. The nanopowders with an average crystallite size of about 30 nm prepared by SPVD were dispersed in 50 ml of acetone in basic media with addition of triethanolamine. The obtained well dispersed and stable suspensions were used for carrying out EPD on 25 mu m thick platinum foils. After deposition, films with thickness of about 22-25 mu m were sintered in air for 15 min at 800, 900 and 1000 degrees C. The structural and microstructural characterization of the sintered thick films was carried out using XRD and SEM, respectively. The thickness of the sintered samples were about 18-20 mu m, which was determined by cross-sectional SEM. Films sintered at 900 degrees C exhibit a dielectric constant, epsilon(r) similar to 18.3 and dielectric loss, tan delta similar to 0.0012 at 1 MHz. The effects of processing techniques (SPVD and EPD) on the structure, microstructure and dielectric properties are reported in detail. The obtained results indicate that the thick films obtained in the present study can be promising for low loss materials for microwave and millimeter wave applications. (C) 2015 Published by Elsevier B.V.

Doped ZnO nanopowders (175 degrees C) impedance data was fitted into two parallel RC circuits to calculate the electrical properties of the varistors. (C) 2015 Elsevier Ltd. All rights reserved.

summary, Zn 1 x Ni x O nanopowders with different Nicontents ofx=0.0,0.04and0.08hasbeensuccessfullysynthesizedvia lowcostsonochemicalreactionmethod.TheeffectofNidopingon Energy structuralevolutionandopticalpropertiesofZnOnanopowdershave been systematically investigated. All the diffractions peaksobserved inXRD patternofpreparednanopowderssamples showspure wurtzite phase for Zn 1 x Ni x O nanostructures with noadditional impurity peaks. Raman spectra of prepared Zn 1 x Ni x Onanopowders reveal a strong peak at 438cm 1 corresponding tofirst order optical mode for wurtzite ZnO structure. The opticalband [31] gap (E g ) was found to decrease with increase in Ni contentfrom 3.33eV(x=0.0),3.26eV(x=0.04)to3.05eV(x=0.08),andthebehaviours was inconsistentwithopticalbehaviourobservedinPLspectra. Tuning of band gap with successful synthesis of ZnOnanopowders on Ni doping demonstrate that Zn 1 x Ni x O nano-powders are useful for various electronic and optical deviceapplications.AcknowledgementsAuthors, BudhendraSinghandAjayKaushalwouldliketothankFundacao para a Ciencia e a Tecnologia for the financial support(Funded by NSRF–POPH) under the grant nos. SFRH/BPD/76184/2011and SFRH/BPD/77598/2011, respectively. Authors are alsothankful to Dr. Suresh Kumar Jakka from Department of Physics,University of Aveiro for PL measurement of prepared samples.References

Single-wall carbon-nanotube (SWNT) reinforced elastomeric epoxy composites were fabricated by adding 0.03 wt% SWNTs and using 0.3 wt% block copolymer to obtain a good dispersion of carbon nanotubes in the epoxy matrix. Young's modulus, fracture stress and strain of the SWNT/epoxy composites with block copolymer were increased by 141%, 127% and 43%, respectively, compared to the pure epoxy resin. Scanning electron microscopy observation revealed that using the block copolymer as a dispersing agent significantly improved both SWNT dispersion in the epoxy matrix and interfacial bonding/load transfer. (C) 2014 Elsevier B.V. All rights reserved.

We report on synthesis of rare earth Er doped ZnO nanoplates via low cost wet precipitation method. The effect of varying Er doping concentration in the range from 3, 5 to 7 wt% on structural, optical and electrical properties of ZnO nanoplates has been successfully investigated. X-ray diffraction (XRD) studies show hexagonal wurtzite phase structure of prepared Er doped ZnO nanoplates. Scanning electron microscopy (SEM) reveals the growth Of nanoplates like structures of the prepared samples. Further, the presence of Er ions doping in ZnO matrix has been confirmed by EDS measurement. A sharp and strong peak at around 435 cm(-1) was observed in Raman spectra of nanoplates which correspond to the high frequency branch of the E2 mode of ZnO. The frequency dependence of dielectric constant (epsilon(r)), dielectric loss (tan delta) and AC conductivity of ZnO nanoplates of different Er doping concentration were measured. The dielectric properties of pure and Er doped ZnO nanoplates follow a behavior based on Maxwell-Weigner model. The AC conductivity was found to decrease with Er doping. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Ceria-based composite electrolytes (50 and 70 vol%) including one mixture of Li and Na carbonates (1:1 molar ratio) were prepared using either pure CeO2 (modest conductor) or Gd-doped ceria (excellent oxide-ion conductor) as ceramic matrix. The composite electrolytes and their phase constituents were tested under pure CO2, air, and H-2 diluted in N-2, at temperatures ranging from 300 to 580 degrees C, to study their electrical performance. Impedance spectroscopy measurements performed under these working conditions were complemented by microstructural characterization. Low temperature (below melting) impedance shows in a clear manner the relevance of the matrix functionality on the performance of these composites, but also reveals additional microstructural and even unusual composite effects. These data were used to test equivalent circuit models derived from the composite constituent properties, and to assess their potential to design composites for target functionalities at higher temperature. (C) 2013 Elsevier Ltd. All rights reserved.

The ZnO thin films (undoped and Fe-doped) deposited by chemical spray pyrolysis technique have been analyzed by X-ray powder diffraction (XRD), atomic force microscopy (AFM) and scanning electron microscopy (SEM). Results show that all the films possess hexagonal wurtzite structure of zinc oxide having crystallite sizes in the range 15-36 nm. On 1 at% Fe doping, the surface roughness of the film increases which favors the adsorption of atmospheric oxygen on the film surface and thereby increase in the gas response. Optical studies reveal that the band gap decreases due to creation of some defect. energy states below the conduction band edge, arising out of the lattice disorder in the doped films. The refractive index of the films decreases on Fe doping and follows the Cauchy relation of normal dispersion. Among all the films examined, the 1 at% Fe-doped film exhibits the maximum response (similar to 72%) at 300 degrees C for 100 ppm concentration of acetone in air. (C) 2013 Elsevier Ltd. All rights reserved.

Silicon nanowires (SiNWs) have been synthesized at temperatures in the range 300-400 degrees C by the hot wire chemical vapor processing (HWCVP) using tin nanotemplate. The tin nano-template is formed by hot wire atomic hydrogen treatment of thermally evaporated Sn films (similar to 300 nm thick) on glass substrates. Silicon nanowires are then grown using hot wire induced dissociation of SiH4 gas over the nanotemplate. Growth conditions like growth time and temperature were varied to study their effect on the tin nanoparticle size and on the silicon nanowire dimensions thereafter. From the observations, it is clear that the nanowire diameters and lengths depend on the size of nanoparticles and the growth time respectively. Though SiNWs were observed to grow at temperatures as low as 300 degrees C, nanowires with a narrow diameter distribution were achieved at 400 degrees C. Raman spectra and transmission electron microscope (TEM) reveal the crystalline nature of the silicon nanowires. (C) 2013 Elsevier Ltd. All rights reserved.

Pure (Na0.50K0.50)(0.95)(Li0.05Sb0.05Nb0.95)O-3 (NKNLS) and CuO doped NKNLS perovskite structured ferroelectric ceramics were prepared by the solid-state reaction method. x wt% of CuO (x = 0.2-0.8 wt%) was added in the NKNLS ceramics. X-ray diffraction patterns indicate that single phase was formed for pure NKNLS while a small amount of second phase (K6Li4Nb10O30 similar to 3%) was present in Cu2+ doped NKNLS ceramics. Dielectric anomalies around the temperatures of 120 degrees C and 350 degrees C have been identified as the ferroelectric-paraelectric transition (orthorhombic to tetragonal and tetragonal to cubic) temperatures for pure NKNLS compound. The electrical behavior of the ceramics was studied by impedance study in the high temperature range. Impedance analysis has shown the grain and grain boundary contribution using an equivalent circuit model. The impedance response in pure and Cu2+ doped NKNLS ceramics could be resolved into two contributions, associated with the bulk (similar to grains) and the grain boundaries. From the conductivity studies, it is found that activation energies are strongly frequency dependent. The activation energy obtained from dielectric relaxation data may be attributed to oxygen ion vacancies. (C) 2012 Elsevier Masson SAS. All rights reserved.

Composite electrodes based on several ceramic oxides were tested for their chemical compatibility and electrochemical performance in systems based on composite Gd-doped ceria + alkaline carbonate electrolytes. Reactivity tests performed at 700 degrees C (accelerated testing conditions), involving the ceramic electrode materials and one mixture of Na and Li carbonates, identified two promising perovskyte-type ceramics, LaCoO3 and La0.8Sr0.2Co0.2Fe0.8O3, as the most stable. Co-pressed and co-sintered cell assemblies (electrode/electrolyte/electrode) involving composite electrodes (perovskytes mixed with alkaline carbonates)were studied in detail by scanning electron microscopy and tested by impedance spectroscopy in air in the temperature range 300-600 degrees C. These tests showed the potential of these composite electrodes for intermediate temperature applications, clearly surpassing in performance standard Au electrodes, here used as reference. (c) 2012 Elsevier Ltd. All rights reserved.

Deposition of copper indium selenide (Cu1-xInxSe2 (0

(La0.6Sr0.4)(0.95)FeO3-delta/Sm0.2Ce0.8O2 (70:30, w/w) and (La0.6Sr0.4)(0.995)Co0.2Fe0.8O3-delta/Gd0.1Ce0.9O2 (50:50, w/w) cathodes screen printed on anode-supported cells were tested for 500h under different conditions by using a Taguchi matrix that combines cathode processing parameters (material composition, thickness, and sintering temperature) and operation conditions (temperature, current density, air flux, air humidification and chromium presence). Activation time increases with current density and varies with sintering temperature. Individual effect of each control factor on cell performance degradation was evaluated: chromium poisoning, air humidity and temperature were classified, in such order, as the most influencing parameters for cathode and cell degradation. Unexpected high degradation rates are reported at 750 degrees C. Limited influence of the type of cathode on long-term cells behavior is observed: LSF/SDC cathodes exhibits, however, higher long-term stability. (C) 2011 Elsevier Ltd. All rights reserved.

Ferroelectric strontium barium niobate (SBN) powder was synthesized by solid-state route. The green compacts were sintered in the temperature range 1250-1350 degrees C in a microwave furnace. The microstructural study, using SEM, revealed the grain size in the range 2-20 mu m without microcracks, depending on the sintering temperature. This is in contrast to that obtained conventionally for sintered SBN powder synthesized by solid-state route, which resulted in duplex microstructure with microcracks [N.S. VanDamme, A.E. Sutherland, L. Jones, K. Bridger, S.R. Winzer, J. Am. Ceram. Soc. 74 (1991) 1785; P.K. Patro, A.R. Kulkarni, C.S. Harendranath, Ceram. Int. 30 (2004) 1405; P.K. Patro, Trans. Ind. Inst. Metals 59 (2006) 229]. Impedance analyzer and ferroelectric hysteresis loop tracer were used for the dielectric, ferroelectric, I-V and electric fatigue measurements. Microwave sintering also resulted in a dielectric maxima epsilon(max) 2590 at 1 kHz (compared to 1103 for conventional sintering [P.K. Patro, A.R. Kulkarni, C.S. Harendranath, Ceram. Int. 30 (2004) 1405]) for the sintering temperature of 1350 degrees C. Similar improvement in microwave-sintered SBN was observed depending on their sintering condition. The origin of this difference is attributed to microstructural differences arising from difference in heating method. In this paper the observed dielectric and ferroelectric behavior have been correlated with different sintering conditions and consequent microstructure due to microwave sintering. (C) 2007

Strontium barium niobate (SBN) ceramics, synthesized through partial co-precipitation, was sintered at-6, 12 and 24 h, respectively, at 1250, 1300 and 1350 degrees C. Structural developments, developments in porosity, grain size, residual stress and crystallographic texture and its effect on dielectric constants were studied at different sintering conditions. The bulk crystallographic texture was largely unaffected by the sintering conditions used, though all other structural parameters evolved through sintering schedule. An effort was made to relate the changes in dielectric constant with the changes in structural parameters. Normal grain growth or changes in residual stress pattern either had relatively insignificant effects on dielectric constant or decoupling the relative effects was difficult from the present set of data. On the other hand, the strongest increase in dielectric constant was achieved through reduced porosity/defects, while abnormal growth caused the largest drop. (c) 2006

Raman spectroscopy is performed on phosphorus implanted silicon wafers with several excitation laser wavelengths ranging from 458 nm to 752.5 nm. The silicon layers were implanted with various implantation energies and doses, ranging below and over the critical dose of amorphization. A factor kappa, relating the Raman intensity of the implanted samples with that of the pure crystalline silicon is introduced, and used ro correlate the effects of ion implantation at different doses, different implantation energies and various annealing temperatures, on the silicon lattice. 117 4 367 374 PT: J TC: 2 J9: NUCL INSTRUM METH B

This paper presents the first results of our molecular beam epitaxy (MBE) experiments on the growth of SrF2 on InP(100) using synchrotron radiation photoelectron spectroscopy (SRPES). Two different ways of preparing the InP surface were used: ex situ HF etching and in situ As treatment. Whereas HF etching provided a clean but rough surface, As treatment led to a flat InP surface with a two-monolayer thick InAs overlayer. The SrF2 grew epitaxially even at room temperature (RT). There was a significant difference in surface roughness of 50 angstrom thick films grown on these two InP surfaces at RT and then annealed at 500-degrees-C for 10 min. The film deposited on the HF etched InP surface had a roughness of 1.8 angstrom, which is rather flat, whereas the film deposited on the As-treated surface had a roughness of 4.5 angstrom, which is rather rough. These roughnesses were determined by atomic force microscopy (AFM). A possible growth model is discussed.