Spray Pyrolysis Deposition Technique Research Articles

Synthesis and Characterization of ZnO-CuO Nanocomposites Thin Film for Optoelectronics Applications

In this work, the spray pyrolysis technique on glass substrates at 480°C was effectively used to generate ZnO, CuO, and n-ZnO/p-CuO nanocomposite thin films. The structure of the ZnO thin films exhibited a hexagonal wurtzite type. In the visible region of the spectrum (400–700 nm), the resulting films had optical transmission ranging from 73% to 83% and optical band gap fluctuations of 3.23 to 3.25 eV. Analysis of the m-lines spectroscopy revealed that the obtained thin layers (ZnO, ZC3, and ZC7) exhibited two modes for both TE and TM polarizations across different molar percentages. This observation confirms the efficacy of the spray pyrolysis deposition technique in producing high-quality waveguides based on ZnO.

Effect of Nickel doping on the Structural, Optical, and electrical properties of titanium dioxide thin films for the application of sensing devices

Thin films of pristine titanium dioxide (TiO2) and doped with different concentrations (0–8) at.% of nickel (Ni) were synthesized onto transparent glass substrates using the spray pyrolysis deposition technique. Field emission scanning electron microscopy revealed the porous and agglomerated surface morphology of the films. X-ray diffractometer demonstrated the anatase crystal structure with a nominal increment of (101) peak. The shifting of peak position revealed the expansion of the unit cell volume from 134.64 to 137.54 (Å)3 whereas crystallite size increased from 34 to 63 nm. Using the Fizeau fringes technique, the thickness of the films was determined between 165 and 190 nm. UV–Vis measurements were employed to examine the optical characteristics of the films. The red shift was observed for 2 at.% Ni content (3.38 eV) while the blue shift was observed for (4–8) at.% Ni content. The wavelength-dependent refractive index and dielectric constant showed anomalous dispersion in the absorption band, representing the transparency of the films. The 4-point probe measurement showed a decreasing trend of resistivity with increasing temperature, whereas the resistivity increased with Ni content. Activation energy indicated a higher amount of adsorbed oxygen in the films due to the high amount of Ni content.

Vis-active TiO2 – g-C3N4 photocatalytic coatings for advanced wastewater treatment and self-cleaning applications

Nowadays, the photocatalysts developed for the advanced wastewater treatment and self-cleaning applications are investigated targeting an up-scaled implementation. This paper reports on Vis-active TiO2 – g-C3N4 composite thin films obtained in-situ using a precursor system deposited by the low-cost spray pyrolysis deposition technique followed by annealing. The films were characterized in terms of crystallinity, morphology, oughness, wettability and transmittance and the results are correlated with the methylene blue (10 ppm) removal efficiency under simulated solar radiation, at low irradiance value. Vis-activation was outlined along with a promising photocatalytic efficiency (~32%) and a good stability indicating that these films could be successfully implemented also as selfcleaning coatings.

Study on effect of thickness and temperature of SnO2 thin film prepared by spray pyrolysis technique

Tin Oxide SnO2 thin films was prepared by using spray pyrolysis deposition technique, They have been deposited on glass substrates with thickness (100-150)nm and in the range of temperatures (400-450-500)0C were studied structure characteristics by using X-ray diffraction (XRD). It was found that all Thin films prepared was polycrystalline in the form tetragonal crystalline quadrant based system .The Optical properties has been studied using transmission spectra and it well found the highest value of optical transmission was 76% in rang (800-900)nm, Then study the effect of change thickness thin films and substrate temperature on the structural and optical properties. Show that the high temperature leads to the regularity of the crystal structure and increase thickness leads to an increase in the particle size, the visual permeability decreases up thickness but increases with high temperature deposition temperature

Investigations on Wide-Gap Al0.21Ga0.79N Channel MOS-HFETs With In0.12Al0.76Ga0.12N Barrier/Buffer and Drain Field-Plate

This work investigates, for the first time, wide-gap Al0.21Ga0.79N channel metal-oxide-semiconductor heterostructure field-effect transistors (MOS-HFETs) with In0.12Al0.76Ga0.12N barrier/buffer and drain field-plate (DFP) designs. High-k and wide-gap Al2O3 was grown as the gate oxide and surface passivation by using non-vacuum ultrasonic spray pyrolysis deposition (USPD) technique. A control device having the same epitaxial layers, except with In0.12Al0.88N barrier/buffer was studied in comparison. Enhanced spontaneous polarization effect, improved interfacial quality, and enhanced carrier confinement have been achieved by using the In0.12Al0.76Ga0.12N barrier/buffer design, which has successfully resulted in improved carrier transport, increased electron concentration, and high current densities. The present In0.12Al0.76Ga0.12N/AlN/Al0.21Ga0.79N MOS-HFET design with (without) DFP design has demonstrated superior maximum drain-source current density (IDS, max) of >1 (>1) A/mm at VDS = 20 V, high saturated drain-source current density at VGS = 0 V (IDSS0) of 791.1 (755) mA/mm, and low specific on-resistance (Ron, sp) of 2.83 (2.81) mΩ/cm2. High device figure-of-merit (FOM) on BVDS2/Ron, sp of 93.7 (75.4) MW/cm2 was also obtained with the three-terminal on-state drain-source breakdown voltage (BVDS) of 515 (460) V. The present design is promisingly advantageous to high-current and high-voltage power-switching circuit applications.

Optimization of erbium percentage molarity on cobalt selenide semiconductor material via spray pyrolysis deposition technique for photovoltaic application

The spray pyrolysis approach was used to successfully synthesize cobalt selenide (CoSe) and cobalt selenide doped erbium (CoSe/Er) materials. The XRD patterns of cobalt selenide (CoSe) and cobalt selenide doped erbium (CoSe/Er) semiconductor materials show strong crystalline peaks at 2θ = 16.03°, 20.29°, 23.89°, 31.92°, and 41.32°, corresponding to diffraction planes (110), (111), (200), (203), and (220). The formation of cobalt selenide material can be determined from the X-ray spectrum angle 16.03°, which corresponds to diffraction plane (110) while the remaining 2 theta angles and diffraction peak demonstrate the formation of cobalt selenide doped erbium. The average size of the crystallites was calculated to be 55.08 nm. Surface morphology analyses indicated homogenous flat nanocrystals at low doping concentrations and massive nanocrystal clusters as doping concentrations increased. The transmittance spectra show that the transmittance of both the CoSe and the Er-doped CoSe thin films significantly increases below 400 nm. The estimated direct bandgap, which is in the 1.53–2.01 eV range and rises with concentration due to a strong quantum effect, makes it appropriate for use in photovoltaic cells.

Spray pyrolyzed fluorinated inorganic-organic passivation for solution-processed a-InZnO thin-film transistors

Reliability is largely considered an important device requirement for commercial electronic devices. In this work, the reliability of solution-processed amorphous indium zinc oxide (a-IZO) thin-film transistors (TFTs) were evaluated through incorporation of inorganic-organic fluorinated polysilsesquioxane (PSQ:F) passivation deposited through spray pyrolysis (SP) and spin coating (SC) techniques. The barrier property of SP and SC PSQ:F passivation layers were examined under positive and negative bias stress tests and both devices revealed superior stability with smaller threshold voltage shift of 0.9 V/−0.4 V and 1.0 V/−0.2 V respectively, after 10000 s. In addition, both PSQ:F films were confirmed to have an excellent hydrophobic property compared to a-IZO film hindering moisture adsorption. Futheremore, XRR data demonstrates that through SP deposition technique, higher density PSQ:F passivation layer was achieved which inhibits the interaction between the ambient atmosphere and the exposed back-channel region efficiently. Enhancement in the reliability and electrical performance of a-IZO TFTs were achieved through combination of additional fluorine additives from PSQ:F with spray pyrolysis deposition technique.

Fabrication of Copper Ferrite Thin Films Using Spray-Pyrolysis Technique and their Structural Characterizations

In the present work, pure copper ferrite (CuFe2O4) thin film has been grown on clean glass substrate by using the spray pyrolysis deposition technique. All the necessary parameters were optimized before the deposition. The deposited thin film was annealed at 500°C for 4 h and then cooled to room temperature. X-ray diffraction (XRD) technique was used to study the phase purity and crystal structure of the sample formed on the thin film. The analysis of the X-ray diffraction pattern reveals the formation of a single-phase cubic spinel structure. The lattice constant and other structural parameters calculated from XRD data are in good agreement with the reported data.

Drug infused Al2O3-bioactive glass coatings toward the cure of orthopedic infection

A unique implant coated substrate with dual-drug-eluting system exhibiting antibacterial, anti-inflammatory, and bone regenerative capacity has been fabricated using spray pyrolysis deposition (SPD) method. Bioglass (BG) and BG-alumina (BG-Al) composites coatings with different concentrations of Al incorporated on BG network over the Cp-Ti substrate were fabricated using SPD technique. Phase purity of BG and BG-Al composites were analyzed by XRD in which Na2Ca2Si3O9 and β-Na2Ca4(PO4)2SiO4) and Na7.15(Al7.2Si8.8O32) phases were formed. Surface morphology of the coated substrates was analyzed by SEM. Uniformity of the coatings were evaluated by surface profilometer and the uniform distribution the nanoparticles were confirmed with Elemental mapping. Systematically, each apatite layer formation on coated substrate was confirmed by immersing the samples for 1, 3, and 7days in simulated body fluid and the needle-like structure was characterized using SEM. Cumulative release of Tetracycline hydrochloride (Tet) antibiotic and Dexamethasone (Dex) anti-inflammatory drug-loaded BG-Al and BG-Al composite-coated substrate were studied for 24h. Antibacterial activity of the coated substrates were evaluated by time-dependent growth inhibition and minimal inhibitory concentration (MIC) assays in which BG-Al and BG-Al composite loaded with Tet showed considerable growth inhibition against S. aureus. Osteoblast-like cells (MG-63) exhibited profound proliferation with no cytotoxic effects which was due to release of Dex drug-coated substrates. Thus, surface modification of Cp-Ti substrate with BG, BG-Al composites coatings loaded with Tet and Dex drug can be considered for post-operative orthopedic implant infection application.

Variation of sulfur concentration on the effective deposition of solution processed ZnS thin films for buffer layer in thin film solar cells

The influence of sulfur concentrations on the growth of ZnS thin films were investigated by low cost chemical spray pyrolysis and chemical bath deposition techniques. The deposited ZnS films showed the major peaks at (111) zinc blende structure from X-ray-diffraction. The FESEM analysis resulted that the deposited films were identified as sphere-like particles for both deposition techniques and the ZnS particle size improved as the sulfur concentration increased in the prepared solutions. The UV analysis showed higher optical transmittance > 70% in the visible region and PL spectra exhibited the defects-free ZnS peaks at blue-green emission bands in the range between 350 nm and 550 nm by both deposition methods. The linear response of I-V characteristics denote to ohmic behavior of the deposited films and the calculated resistivity of the films were in the range of 107Ω.cm and 108 Ω.cm. Hence, the characterized results suggest that the deposited ZnS films with increasing sulfur concentration using both deposition methods show optimum properties for buffer layers in thin film photovoltaics.

Design and Fabrication of Nanostructure TiO2 Doped NiO as A Gas Sensor for NO2 Detection

In this paper, thin films of undoped and nickel oxide (NiO) doped titanium dioxide (TiO2) were prepared using the chemical spray pyrolysis deposition (CSP) technique, with different concentrations of nickel oxide (NiO) in the range (3-9) wt%. The morphological, structural, electrical, and sensing properties of a gas of the prepared thin films were examined. XRD measurements showed that TiO2 films have a polycrystalline structure. AFM analysis showed that these films have a regular structure both before and after doping . The roughness of these films decreased after adding impurities but then the opposite of that took place. The electrical and gas sensing properties of titanium dioxide was also affected after doping. The highest sensitivity value was obtained at doping concentration of 5wt% and working temperature 473ºK.

Physicochemical characterization and catalytic performance of Fe doped CuS thin films deposited by the chemical spray pyrolysis technique

The thin films Fe doped copper sulphide Cu1−xFexS (CFS) (x = 0.01, 0.03, 0.05, and 0.07) were elaborated by spray pyrolysis deposition technique. The characterization by XRD and SEM of the thin films shows a Covellite CuS single phase without formation of other phases. The structure is a simple hexagonal with unit cell dimension, a = b = 3.79 A and c = 16.34 A. The Analysis of the UV–Vis spectra reveals that the energy band gap has been decreased from 2.47 to 1.98 eV with the increase of Fe concentration. The absorption coefficients of CFS films have increased from 1.155 × 105 to 1.712 × 105 cm−1. It has demonstrated that a right band gap with a right band edge alignment at a pH value for Fe-doped CFS can boost the material application as a photocatalyst for the visible light. According to this study, CFS (0.07) thin films for a pH = 3 solutions is a promising material for photocatalysis application for water splitting to hydrogen-oxygen production. Nevertheless, we demonstrate that the formation of straddling gap heterostructure for CuS and CFS for a pH solution between 7 and 8 induces the production of oxygen and hydrogen.

Structural, Opticaland Morphological Properties Of Zn And Mg Co-Doped V2O5 Thin Filmnanostructures

The research study reveals metallic co-doping of Zinc(Zn) and Magnesium (Mg) on vanadium pentoxide(V2O5) thin film nanostructures by spray pyrolysis deposition technique. The studyfindings have been made into how the morphological, structural and optical properties of the materials change for the different co-doping percentage of 1%,3%,5%10% of Zn-Mg. X-ray diffraction (XRD)clearly showsan orthorhombic crystalline structure with polycrystalline nature.The dopantZn and Mginfused into the V2O5 matrixand is confirmed by EDAX images. A field emission scan electron microscope was used to examine surface morphology whichreveals that grain structure has beenmodified by increasing the doping content. It is evident from theatomic force microscopy (AFM) images that the effect of Zn and Mg on V2O5 thin filmshave enhanced surface roughness.The transmittance and energy bandgap (Eg) of the film found to be decreased with an increase in doping concentration whereas absorbance varieswith doping levels.The research findings suggest that the Zn-Mg co-doped V2O5 thin films could be a potential source for energy,optical and sensor-based device applications.

Spray Pyrolyzed TiO2 Embedded Multi-Layer Front Contact Design for High-Efficiency Perovskite Solar Cells

HighlightsIndustrially viable bottom-up spray pyrolysis deposition technique was used to prepare the highly compact TiO2 film, which is a vital element for the multi-layer front contact.The optimization of the front contact is presented by fabricating reproducible and efficient perovskite solar cellsMulti-layer front contact is applied to realize efficient perovskite single-junction and perovskite/perovskite tandem solar cells, where optics and electrical effects of solar cells are studied by optically coupled 3D electromagnetic simulations.

Undoped and Nickel-Doped Zinc Oxide Thin Films Deposited by Dip Coating and Ultrasonic Spray Pyrolysis Methods for Propane and Carbon Monoxide Sensing Applications.

Undoped and nickel-doped zinc oxide thin films were deposited on sodalime glass substrates by utilizing dip coating and ultrasonic spray pyrolysis deposition techniques. In both cases zinc acetate and nickel acetylacetonate were used as zinc precursor and nickel dopant source, respectively. XRD analysis confirms the ZnO wurtzite structure with (002) as the preferential orientation.SEM studies show the formation of two types of morphologies, primarily a porous spherical grains with a grain size distribution from 40 to 150 nm and another, rose-like structures with size distribution from 30 to 200 nm, based on different deposition techniques utilized. The elemental depth profiles across the films were investigated by the secondary-ion mass spectrometry (SIMS). Different gas sensing responses of all ZnO films were obtained for both propane and carbon monoxide gases, at different gas concentrations and operating temperatures. The highest sensing response (~6) for undoped ZnO films was obtained for films deposited by ultrasonic spray pyrolysis (USP). Nevertheless, the highest sensing response (~4 × 104) for doped ZnO films was obtained for films deposited by dip coating method. The behavior of sensing responses is explained in detail based on the morphological properties and the amount of Ni impurities incorporated into the crystal lattice.

Metal Oxide Thin Films for Chemical and UV Sensors

Highly sensitive and fast responding Titanium Dioxide (TiO2) nano sensors are developed for CO gas and other materials such as methanol and methane. Nano-porous TiO2 thin films are prepared from a colloidal solution of TiO2 nano particles (P-25) in ethanol by spray pyrolysis deposition (SPD) technique. Initially the TiO2 films are grown at 60 0C and after the deposition, backed in an oven at 65 0C overnight and then annealed at 450 0C for one hour to get anatase phase. The surface morphology and structural properties of the films are studied using SEM and XRD. For sensor applications, two gold contacts separated by 0.25 mm are made on quartz substrate. A sensing and testing system has been developed based on change in the resistance of the TiO2 film. CO gas (2% in Air) through mass flow controller is used for repeated five minutes cycles of air and CO at different temperatures in the range of 200 0C to 350 0C. Response and sensitivity of the sensor has been studied. Same apparatus and sensor is also used to detect UV, methane and methanol respectively.

Fe Doped Mno<sub>2</sub> Nanostructured Thin Films: Synthesis and Characterization for Biosensor applications

Iron (Fe), a magnetic transition metal, doped manganese oxide (MnO2) nanostructured thin films were deposited onto glass substrates by a spray pyrolysis deposition technique at 450oC substrate temperature for glucose sensing performance. Fe concentration greatly affects the film surface morphology. The film was found to be more compact and porous for 4 at % Fe doping. The glucose response was measured by electrical four probe method using the pure MnO2 and 2, 4, 6, 8 at% Fe doped MnO2 thin films as an active electrode. It was determined that 4 at % Fe: MnO2 thin film with 20 nm crystallite size has high sensitivity, fast glucose response and recovery time. Optical band gap measurement indicated that the sensitivity increased as the band gap decreased up to 4 at% Fe concentration. The highest glucose sensing response was recorded about 29 % in 5 minutes.
 Bangladesh Journal of Physics, 27(1), 1-12, June 2020

Mechano-adaptive thin film of graphene-based polymeric nanocomposite for enhancement of lubrication properties

Intriguing low frictional properties of 2D materials can be harnessed for thin-film lubrication in small-scale devices by making their mechano-adaptive coatings. Herein, the reduced graphene oxide-polystyrene (rGO-PS) nanocomposite synthesized by single-step chemical processing of graphene oxide and polystyrene is applied to prepare self-lubricating thin film over the silicon substrate. The non-covalent π-π interaction between the aromatic rings of polystyrene and the π-electron network of rGO furnished excellent interfacial adhesion and extended the mechanical strengthening and lubrication properties. The interfacial interaction is further supported by higher glass transition and thermal decomposition temperatures of the rGO-PS nanocomposite. The rGO-PS thin film with a uniform thickness of 850 nm is coated on a silicon surface by a spray pyrolysis deposition technique. The rGO-PS thin film showed significantly low friction (μ = 0.12) compared to the silicon substrate (μ = 0.6). The microscopic and spectroscopic analyses confirmed the deposition of a graphene-based thin film on the counter interface of the steel ball. Furthermore, the rGO-PS thin film couldn’t damage/rupture even after 100,000 cyclic contacts, which revealed its remarkable wear-resistivity. The excellent mechano-adaptability and low frictional properties of rGO-PS thin film promise the potential of 2D nanomaterials for thin-film lubrication applications.

PREPARATION OF MIXED In2O3 – CdO THIN FILMS BY CSP TECHNIQUE FOR LIGHT SENSING

In this work, chemical spray pyrolysis deposition (CSP) technique was used to prepare a mixed In2O3-CdO thin films with different CdO content (10, 30 and 50)%volume ratio on glass substrates at 150 ᵒC substrate temperature. The surface morphology and structural properties were measured to find the optimum conditions to improve thin films properties for using as photo detector. Current –Time, the sensitivity and response speed vary for each mixture. Samples with 10% vol. CdO content has square pulse response with average rise time nearly 1s and fall time 1s.

Role of Fe doping on structural and electrical properties of MnO2 nanostructured thin films for glucose sensing performance

Iron (Fe) doped manganese dioxide (MnO2) nanostructured thin films (Fe: MnO2) were prepared by a spray pyrolysis deposition technique to explore their morphological, structural, and electronic properties suitable for glucose sensing abilities. Many useful characteristics were observed in the growth process and phase transformation due to the addition of Fe concentration in the range of 0–8 at %. Fe concentration strongly influenced the crystallite size of MnO2 analyzed by field emission scanning electron microscope. Powder X-ray diffraction (PXRD) pattern of the deposited thin films showed the tetragonal crystal structure with a body-centered space group (I41/acd) having lattice parameters a = b = 9.787 Å and c = 2.865 Å and well agrees with the JCPDS card file no. 44–0141. Crystallite size was measured ranging from 20 nm to 30 nm using Debye Scherer relation. Williamson-Hall plot results indicated the appearance of strain for Fe doping. Maximum carrier concentration was found at 4 at% Fe concentration using Hall Effect measurement. The highest glucose-sensing response was recorded at about 29% at 5 min for 4 at% Fe concentration.