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Nanostructured Al Doped SnO2 Films Grown onto ITO Substrate via Spray Pyrolysis  [PDF]
M. Benhaliliba,C.E. Benouis,Y.S. Ocak,F. Yakuphanoglu
Journal of Nano- and Electronic Physics , 2012,
Abstract: We report on nanostructured films of Al doped tin oxide grown by facile spray pyrolysis route, and their physical properties were investigated. The sprayed films were grown onto indium tin oxide (ITO) substrate at 300 °C from the precursor (SnCl4, 5H2O). The content of Al is kept at 3 % in the solution. Structural, optical, electrical and surface properties were investigated. X-rays pattern reveals polycrystalline structure and SnO2 phase occurence. The visible transmitance exceeds 85 %, the band gap is found to be 3.7 eV. Nanotips were observed by 3D atomic force microscope (AFM) observation. Using the Hall effect measurements system (HMS), the films exhibit very low resistivity found to be 9.85 10 – 5 .cm, a high electron concentration is around 1021 cm – 3, and the mobility reaches the value of 20 cm2/Vs. We report on nanostructured films of Al doped tin oxide grown by facile spray pyrolysis route, and their physical properties were investigated. The sprayed films were grown onto indium tin oxide (ITO) substrate at 300 °C from the precursor (SnCl4, 5H2O). The content of Al is kept at 3 % in the solution. Structural, optical, electrical and surface properties were investigated. X-rays pattern reveals polycrystalline structure and SnO2 phase occurence. The visible transmitance exceeds 85 %, the band gap is found to be 3.7 eV. Nanotips were observed by 3D atomic force microscope (AFM) observation. Using the Hall effect measurements system (HMS), the films exhibit very low resistivity found to be 9.85 10 – 5 .cm, a high electron concentration is around 1021 cm – 3, and the mobility reaches the value of 20 cm2/Vs. We report on nanostructured films of Al doped tin oxide grown by facile spray pyrolysis route, and their physical properties were investigated. The sprayed films were grown onto indium tin oxide (ITO) substrate at 300 °C from the precursor (SnCl4, 5H2O). The content of Al is kept at 3 % in the solution. Structural, optical, electrical and surface properties were investigated. X-rays pattern reveals polycrystalline structure and SnO2 phase occurence. The visible transmitance exceeds 85 %, the band gap is found to be 3.7 eV. Nanotips were observed by 3D atomic force microscope (AFM) observation. Using the Hall effect measurements system (HMS), the films exhibit very low resistivity found to be 9.85 10 – 5 .cm, a high electron concentration is around 1021 cm – 3, and the mobility reaches the value of 20 cm2/Vs.
Ultrasonic spray pyrolysis deposition of SnSe and SnSe2 using a single spray solution
Ultrasonic spray pyrolysis deposition of SnSe and SnSe[sub_s]2[sub_e] using a single spray solution

Jorge Sergio Narro-Rios,Manoj Ramachandran,Dalia Mart&#,nez-Escobar,Aar&#,n S&#,nchez-Ju&#,rez,
Jorge Sergio Narro-Rios
,Manoj Ramachandran,Dalia Mart&#,nez-Escobar,Aar&#,n S&#,nchez-Ju&#,rez

半导体学报 , 2013,
Abstract: Thin films of SnSe and SnSe2 have been deposited using the ultrasonic spray pyrolysis (USP) technique. To the best of our knowledge this is the first report of the deposition of SnSe and SnSe2 thin films using a single spray solution. The use of a single spray solution for obtaining both a p-type material, SnSe, and an n-type material, SnSe2, simplifies the deposition technique. The SnSe2 thin films have a bandgap of 1.1 eV and the SnSe thin films have a band gap of 0.9 eV. The Hall measurements were used to determine the resistivity of the thin films. The SnSe2 thin films show a resistivity of 36.73 Ω·cm and n-type conductivity while the SnSe thin films show a resistivity of 180 Ω·cm and p-type conductivity.
Synthesis of Core-Shell Si /Carbon Nanofibers on Silicon Substrates by Ultrasonic Spray Pyrolysis
Jianhui Zhang,Naoki Kishi,Tetsuo Soga,Takashi Jimbo,Takayoshi Tanji
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/259806
Abstract: We synthesized the core-shell SiO/carbon nanofibers with diameters of 200–300 nm using ultrasonic spray pyrolysis with a phosphorus/ethanol mixture. High-resolution transmission electron microscopy (HRTEM) and energy-dispersive spectroscopy (EDS) investigations confirmed the core-shell structure, which consisted of a core of SiO and a shell of amorphous carbon. The phosphorus atoms corroded the entire silicon substrate surface, and the Si-P liquid-catalyzed the solid-liquid-solid mechanism is proposed to explain the growth of the core-shell SiO/carbon nanofibers.
Effect of the Substrate Movement on the Optical Properties of ZnO Thin Films Deposited by Ultrasonic Spray Pyrolysis  [PDF]
Ebru Gungor,Tayyar Gungor
Advances in Materials Science and Engineering , 2012, DOI: 10.1155/2012/594971
Abstract: Using a modified ultrasonic spray pyrolysis (USP) system, ZnO thin films were deposited on the substrate moved back and forth (ZO1) and rotated (ZO3) as well as fixed (ZO2) in the conventional USP technique. Prepared thin films are pure ZnO with a preferred crystalline orientation of (0 0 2) in the hexagonal wurtzite structure. Diffraction angle shift implies a decrease lattice parameter along c-axis and a-axis 0.2% and 0.3%, respectively. Maximum strain has been found for ZO1 which is about (?) 0.17%. These strain values show that presence of compressive strain due to moving substrates as depositing ZnO films. The film deposition process on the rotated quartz substrate isprovided to obtain the thinner film. The grain size and root-mean- square value of roughness increase with thickness. Strong UV emission was observed at ~390?nm assigned to the band gap transition from photoluminescence measurements. Energy shifted about 39?meV for ZO3 sample with respect to that of ZO2 film deposited in conventional USP system. This behaviour is confirmed with (002) diffraction peak shifting. So, the compressed lattice will provide a wider band gap for these films. phonon frequency values have not given a considerable shifting. 1. Introduction Zinc oxide is one of the few metal oxides which can be used in numerous technological applications such as photoelectronic devices, information storage, gas sensors, and catalysis [1–4]. Recently, zinc oxide (ZnO) thin film has received more and more attention, because of its less toxic and low cost. ZnO thin films can be prepared by using various deposition techniques, such as reactive evaporation [5], RF sputtering [6], chemical vapor deposition (CVD) [7], ultrasonic spray pyrolysis (USP) [8], and sol-gel method [9]. The ultrasonic spray pyrolysis method is one of the preferred method for the deposition of thin films of metallic oxides such as the ZnO material. In this method, various processing parameters such as substrate temperature, the distance between nozzle and substrate, precursor solution flow rate, spraying geometry, and carrier gas flow rate can be optimized in order to determine how these affected morphology, stoichiometry, crystallography, electrical properties, and optical properties of deposited thin films. When the optimum parameters are obtained, a starting solution, containing Zn precursor, is sprayed by means of a ultrasonic nozzle, assisted by a carrier gas, over a fixed hot substrate. The substrate is very important for the growth of thin films in terms of the lattice and thermal mismatching between the
Synthesis of Li2Ti3O7 Anode Materials by Ultrasonic Spray Pyrolysis and Their Electrochemical Properties  [PDF]
Takashi Ogihara,Takayuki Kodera
Materials , 2013, DOI: 10.3390/ma6062285
Abstract: Ramsdellite-type lithium titanate (Li 2Ti 3O 7) powders were synthesized by performing ultrasonic spray pyrolysis, and their chemical and physical properties were characterized by performing Scanning Electron Microscope (SEM), powder X-ray Diffraction (XRD), and Inductively Coupled Plasma (ICP) analyses. The as-prepared Li 2Ti 3O 7 precursor powders had spherical morphologies with hollow microstructures, but an irregularly shaped morphology was obtained after calcination above 900 °C. The ramsdellite Li 2Ti 3O 7 crystal phase was obtained after the calcination at 1100 °C under an argon/hydrogen atmosphere. The first rechargeable capacity of the Li 2Ti 3O 7 anode material was 168 mAh/g at 0.1 C and 82 mAh/g at 20 C, and the discharge capacity retention ratio was 99% at 1 C after the 500th cycle. The cycle performance of the Li 2Ti 3O 7 anode was also highly stable at 50 °C, demonstrating the superiority of Li 2Ti 3O 7 anode materials reported previously.
Efficient Visible Light Photocatalytic Oxidation of NO on F- and N-Codoped Spherical Synthesized via Ultrasonic Spray Pyrolysis  [PDF]
Jianhui Huang,Wahkit Cheuk,Yifan Wu,Frank S. C. Lee,Wingkei Ho
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/753429
Abstract: The fluorine- and nitrogen-codoped TiO2 was synthesized by ultrasonic spray pyrolysis method with titanium tetrafluoride and urea as precursor. The codoped TiO2 was characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance spectroscopy (DRS), and X-ray photoelectron spectroscopy (XPS). Nitric oxide (NO) photocatalytic oxidation in gas-phase medium was employed as a probe reaction to evaluate the photocatalytic reactivity of the catalysts. The results indicated that spherical codoped TiO2 photocatalysts with unique puckered surface were obtained by this method. The codoped catalysts have solely anatase crystalline structure. The optical characterization of the codoped catalysts showed that the codoped samples could be excited by visible light photons in the 400–550?nm and could efficiently oxidize NO under visible light irradiation. The mechanism of special morphology formation of prepared codoped TiO2 structure is also discussed. 1. Introduction Growing knowledge about the indoor air quality (IAQ) has validated it as one of the major risks of the human health as people spend more than 80% of their time indoors in most countries [1]. Thus, more and more attentions have been drawn into developing a green process of eliminating pollutants from indoor air. Several physical and chemical methods for treating the pollutant in the indoor air have been studied extensively, including adsorption [2, 3], ozonation [4], plasma [5], and photocatalytic oxidation [6–9]. Among these, semiconductor-mediated photocatalysis is one of the most efficient destructive technologies because of its high redox ability, nonselectivity, at-room temperature, and atmospheric pressure. For decades, titanium dioxide (TiO2) has been accepted as one of the most promising photocatalysts owning to its intrinsic properties such as inexpensiveness, high chemical stability, and low toxicity. Unfortunately, a major obstacle in the popularization of TiO2 is its large band gap (3.2?eV) which work only under specific UV light region ( ?nm), hence, practically ruling out most of the solar energy for the environmental remediation. Thus, considerable efforts have been devoted to modified TiO2 in order to broaden the light response range of TiO2-base photocatalysts which is still a significant issue in both academic and practical applications. Doping TiO2 with various elements has been proved as an effective method to optimize the band structure of TiO2, and thereby in resulting to be a visible-light sensitive
Fabrication of Bi-Doped Spheres with Ultrasonic Spray Pyrolysis and Investigation of Their Visible-Light Photocatalytic Properties  [PDF]
Jianhui Huang,Wahkit Cheuk,Yifan Wu,Frank S. C. Lee,Wingkei Ho
Journal of Nanotechnology , 2012, DOI: 10.1155/2012/214783
Abstract: Bismuth-doped TiO2 submicrospheres were synthesized by ultrasonic spray pyrolysis. The prepared bismuth-doped titania was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-visible diffuse reflectance spectroscopy (UV-vis DRS), and X-ray photoelectron spectroscopy (XPS). Aqueous photocatalytic activity was evaluated by the decomposition of methyl orange under visible-light irradiation. The results indicate that doping of bismuth remarkably affects the phase composition, crystal structure, and the photocatalytic activity. The sample with 2% Bi exhibits the optimum photocatalytic activity. 1. Introduction Photocatalytic oxidation of pollutants has increasing interests in recent years because of its advantages such as high redox capability, nonselectivity, and efficient solar utilization. Different kinds of photocatalytic materials have been studied such as metal oxides, nitrides, and sulfides [1–7]. Among them, TiO2 is the most commonly used photocatalyst owing to its high redox power, photostability, chemical inertness and low cost. However, the relatively low quantum efficiency of TiO2 photocatalysts limits its real application. To overcome this problem, a lot of efforts have been paid to improve the photocatalytic efficiency of TiO2 from the viewpoint of practical use. It has been reported that the crystal size, specific surface area, morphology, and texture have great effects on the photocatalytic properties of semiconductors. Nano/microspheres structure has attracted great interests due to their thermodynamically favorable state in terms of surface energy. Recent researches have demonstrated their potential application in many fields such as photonic crystals [8], biomedicine [9, 10], sensing [11, 12], and solar cells [13, 14]. In particular, some studies found that the nano/microspheres structure of semiconductor have promising properties in the region of photocatalysis [15–17]. Various approaches have been used for the preparation of spherical semiconductor materials. The most common approach is based on the use of various removable templates. The removal of template materials is complex and usually requires high temperature processes or wet chemical etching, which is expensive and not easy for mass application. Therefore, it is promising to develop a simple and inexpensive way without using template for the preparation of semiconductor nano/microspheres. Many reports have shown that the photocatalytic properties of TiO2 can be modified strongly by doping with different elements.
Novel morphology of needle-Like nanoparticles of Na2Mo2O7 synthesized by using Ultrasonic spray pyrolysis
Valid?i?, Ivana Lj.;Mitri?, Miodrag;
Materials Research , 2013, DOI: 10.1590/S1516-14392012005000142
Abstract: low-temperature method for the synthesis of novel morphology of needle-like nanoparticles of disodium dimolybdate (na2mo2o7) in the process of ultrasonic spray pyrolysis (usp) using aqueous solutions of thermodynamically stable molybdenum (vi) oxide clusters as precursor is described. needle-like na2mo2o7 particles were obtained and collected in toluene, while centrifugation was employed to isolate solid material from solution. the scanning electron microscopy (sem) confirmed that the morphology of the synthesized na2mo2o7 particles is needle-like collected into bundles. the x-ray powder diffraction (xrpd) analysis revealed appearance of orthorhombic na2mo2o7, synthesized at 300 °c. by comparing the xrpd pattern of the synthesized needle-like na2mo2o7 powder obtained in the process of usp with the xrpd pattern simulated for randomly-distributed crystallites by planes, the most prefered growth plane of needle-like nanoparticles were found.
Thulium and ytterbium-doped titanium oxide thin films deposited by ultrasonic spray pyrolysis  [PDF]
S. Forissier,H. Roussel,P. Chaudouet,A. Pereira,J. -L. Deschanvres,B. Moine
Physics , 2012, DOI: 10.1007/s11666-012-9813-7
Abstract: Thin films of thulium and ytterbium-doped titanium oxide were grown by metal-organic spray pyrolysis deposition from titanium(IV)oxide bis(acetylacetonate), thulium(III) tris(2,2,6,6-tetramethyl-3,5-heptanedionate) and ytterbium(III) tris(acetylacetonate). Deposition temperatures have been investigated from 300{\deg}C to 600{\deg}C. Films have been studied regarding their crystallity and doping quality. Structural and composition characterisations of TiO2:Tm,Yb were performed by electron microprobe, X-ray diffraction and Fourier transform infrared spectroscopy. The deposition rate can reach 0.8 \mum/h. The anatase phase of TiO2 was obtained after synthesis at 400{\deg}C or higher. Organic contamination at low deposition temperature is eliminated by annealing treatments.
Equilibrium State of Anatase to Rutile Transformation for Titanium Dioxide Film Prepared by Ultrasonic Spray Pyrolysis Technique  [PDF]
Ghassem Kavei, Auppatham Nakaruk, Charles Chris Sorrell
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.26096
Abstract: Titanium dioxide thin films were deposited on (0001) α-quartz substrate by spray pyrolysis method. The method which an aerosol of Titanium Butoxide, generated ultrasonically, was sprayed on the substrate at temperature of 400°C, kept at this temperature for periods of 3, 13, 19 and 39 hours. The developed films at a crystal phase correspond to the TiO2 anatase and rutile phases. Their surface roughness increased by annealing the samples at 600, 800 and 1000°C. Deposited film annealed at 1000°C showed preferable orientation in (110) direction. The crystal evolution and crystallographic properties of this material was studied by Lotgering method, X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The study revealed that the deposition process was nearly close to the classical Chemical Vapour Deposition (CVD) technique that is generally employed to produce films with smooth surface and good crystalline properties with a thickness of about 1 µm, as measured by Focused Ion Beam.
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