Growth of sprayed nanostructured copper (I) iodide (CuI) thin films at different precursor solution concentration

Control over crystallographic orientation in thin films is important, particularly with highly anisotropic structures. Because of its ferroelectric nature, the layered perovskite La2Ti2O7 has interesting piezoelectric and electrooptic properties that may be exploited when films are highly textured. Sol-gel films with an orientation factor of greater than 95% were fabricated without relying on epitaxial (lattice-matching) growth from the substrate. Film orientation and crystallization were confirmed by x-ray diffraction, scanning electron microscopy, atomic force microscopy, and optical measurements. The particle sizes in all precursor solutions were measured by dynamic light scattering experiments. Experimental results indicate that film orientation is a function of precursor solution concentration, size of the molecular clusters in the solution, and film thickness.

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Influence of precursor solution concentration on the structural, optical and humidity sensing properties of spray-deposited TiO2thin films

Journal of Semiconductors ◽

10.1088/1674-4926/39/12/122003 ◽

2018 ◽

Vol 39 (12) ◽

pp. 122003 ◽

Cited By ~ 2

Author(s):

Dipak L Gapale ◽

Sandeep A Arote ◽

Balasaheb M Palve ◽

Ratan Y Borse

Keyword(s):

Precursor Solution ◽

Solution Concentration ◽

Humidity Sensing ◽

Sensing Properties ◽

Precursor Solution Concentration ◽

Humidity Sensing Properties

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Effect of Solution Conditions on the Properties of Sol–Gel Derived Potassium Sodium Niobate Thin Films on Platinized Sapphire Substrates

Nanomaterials ◽

10.3390/nano9111600 ◽

2019 ◽

Vol 9 (11) ◽

pp. 1600 ◽

Cited By ~ 2

Author(s):

Alexander Tkach ◽

André Santos ◽

Sebastian Zlotnik ◽

Ricardo Serrazina ◽

Olena Okhay ◽

...

Keyword(s):

Thin Films ◽

Grain Size ◽

Low Cost ◽

Sol Gel ◽

Precursor Solution ◽

Dissipation Factor ◽

Solution Concentration ◽

Potassium Sodium Niobate ◽

Sapphire Substrates ◽

Average Grain Size

If piezoelectric micro-devices based on K0.5Na0.5NbO3 (KNN) thin films are to achieve commercialization, it is critical to optimize the films’ performance using low-cost scalable processing conditions. Here, sol–gel derived KNN thin films are deposited using 0.2 and 0.4 M precursor solutions with 5% solely potassium excess and 20% alkali (both potassium and sodium) excess on platinized sapphire substrates with reduced thermal expansion mismatch in relation to KNN. Being then rapid thermal annealed at 750 °C for 5 min, the films revealed an identical thickness of ~340 nm but different properties. An average grain size of ~100 nm and nearly stoichiometric KNN films are obtained when using 5% potassium excess solution, while 20% alkali excess solutions give the grain size of 500–600 nm and (Na + K)/Nb ratio of 1.07–1.08 in the prepared films. Moreover, the 5% potassium excess solution films have a perovskite structure without clear preferential orientation, whereas a (100) texture appears for 20% alkali excess solutions, being particularly strong for the 0.4 M solution concentration. As a result of the grain size and (100) texturing competition, the highest room-temperature dielectric permittivity and lowest dissipation factor measured in the parallel-plate-capacitor geometry were obtained for KNN films using 0.2 M precursor solutions with 20% alkali excess. These films were also shown to possess more quadratic-like and less coercive local piezoelectric loops, compared to those from 5% potassium excess solution. Furthermore, KNN films with large (100)-textured grains prepared from 0.4 M precursor solution with 20% alkali excess were found to possess superior local piezoresponse attributed to multiscale domain microstructures.

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EFFECTS OF SPRAY PYROLYSIS DEPOSITION PARAMETERS ON MORPHOLOGICAL, OPTICAL AND STRUCTURAL PROPERTIES OF WO3 NANOSTRUCTURED THIN FILMS

Surface Review and Letters ◽

10.1142/s0218625x19502032 ◽

2020 ◽

Vol 27 (09) ◽

pp. 1950203

Author(s):

ALI AKHAVAN MAVARDIANI ◽

MOHAMMAD BAGHER RAHMANI

Keyword(s):

Thin Films ◽

Surface Morphology ◽

Spray Pyrolysis ◽

Precursor Solution ◽

Cost Effective ◽

Solution Concentration ◽

Visible Range ◽

Glass Substrates ◽

Deposition Parameters ◽

Vis Spectroscopy

In this experimental research, tungsten trioxide (WO3) thin films were deposited using ammonium tungstate ((NH4)2WO4) by a simple and cost-effective technique of spray pyrolysis on top of glass substrates. The surface morphology, structural and optical properties of prepared samples were studied using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) pattern analysis and UV–Vis spectroscopy techniques, respectively. Studied deposition parameters were: substrate temperature (300, 350, 400, 450 and 500∘C), concentration of the precursor solution (0.01, 0.02, 0.04, 0.08, 0.1 and 0.2[Formula: see text]M), volume of the precursor solution (50, 100, 150 and 200[Formula: see text]mL) and the effect of pulsed spraying at different concentrations (0.01, 0.1 and 0.2[Formula: see text]M). FESEM images showed that the surface morphology has formed like nested micro-fibrous rings with a uniform distribution all over the surface. The XRD patterns revealed that increasing the solution concentration to 0.2[Formula: see text]M shows some peaks which can be attributed to WO3 with the hexagonal crystal structure. Transmission spectra of the samples indicate that all of the prepared samples are transparent in the visible range, with the calculated direct bandgap ranging from about 2.93[Formula: see text]eV to 3.96[Formula: see text]eV, depending on the deposition conditions.

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Impact of Perovskite Composition on Film Formation Quality and Photophysical Properties for Flexible Perovskite Solar Cells

Molecules ◽

10.3390/molecules25030732 ◽

2020 ◽

Vol 25 (3) ◽

pp. 732 ◽

Cited By ~ 3

Author(s):

Guangdong Li ◽

Xiaoping Zou ◽

Jin Cheng ◽

Dan Chen ◽

Yujun Yao ◽

...

Keyword(s):

Solar Cells ◽

Film Formation ◽

Photophysical Properties ◽

Perovskite Solar Cells ◽

Precursor Solution ◽

Solution Concentration ◽

Precursor Solution Concentration ◽

Composition Optimization ◽

A Site ◽

Low Temperature Process

In recent years, flexible perovskite solar cells have drawn tremendous attention in the field of wearable devices, and optimization of perovskite composition plays an important role in improving film quality and photophysical properties. At present, some researchers have only studied A-site organic cations mixing or X-site halide anions mixing in the ABX3 structure of perovskite, but there are few reports on co-mixing of A-site and X-site ions in flexible perovskite solar cells. In this paper, we mainly try to study the effects of different concentrations of mixed formamidine methylamine halide (FAxMA1-xBrxClyI1-x-y) precursor solutions on the quality and photophysical properties of perovskite films under low temperature process. We conclude that the film quality and photophysical properties reached the best results when the optimized precursor solution concentration was 60:6:6. The investigation on composition optimization in this experiment laid the foundation for the improvement of the performance of flexible perovskite solar cells. We also use the results of this experiment to prepare flexible perovskite solar cells based on carbon electrodes, which are expected to be applied in other flexible optoelectronic or electro-optical devices.

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Structural and Optical Studies of Molarity Based ZnO Thin Films

Nano Hybrids and Composites ◽

10.4028/www.scientific.net/nhc.17.140 ◽

2017 ◽

Vol 17 ◽

pp. 140-148 ◽

Cited By ~ 2

Author(s):

A. Jacquiline Regina Mary ◽

S. Arumugam

Keyword(s):

Thin Films ◽

Grain Size ◽

Visible Region ◽

Precursor Solution ◽

Hexagonal Wurtzite Structure ◽

Solution Concentration ◽

Molar Concentration ◽

Zno Thin Films ◽

Zno Films ◽

Average Grain Size

Zinc Oxide thin films were prepared for different precursor solution molarities from 0.025M to 0.1M by spray pyrolysis deposition technique. A comprehensive study was carried out to realize the effect of concentration of precursor on ZnO thin films. The optimized temperature of the glass substrate was 300°C. From the XRD data it is inferred that the films are polycrystalline and hexagonal wurtzite structure . The degree of preferred orientation were along diffraction planes (100), (002) and (101) for all the ZnO films. The intensity of the diffraction peak prepared with 0.1M concentration is higher than those prepared at lower concentrations. The grain size (D) was calculated using Debye-Scherrer formula. It was found that the average grain size increases, when the molar concentration increases. As the solution concentration increases, the band gap decreases. The films are transparent in the visible region (85%), and the transmittance decreases as the molar concentration increases, which is caused by optical scattering at grain boundaries.

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Desulfurization and Regeneration Performance of Sorbent Prepared by Subcritical Water Impregnation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.743-744.443 ◽

2013 ◽

Vol 743-744 ◽

pp. 443-448

Author(s):

Hao Chen Qin ◽

Lian Wei Liu ◽

Wei Ping Si ◽

Li Ping Chang ◽

Wei Ren Bao ◽

...

Keyword(s):

Subcritical Water ◽

Precursor Solution ◽

Nitrogen Adsorption ◽

Solution Concentration ◽

X Ray Diffraction ◽

Active Components ◽

Precursor Solution Concentration ◽

Impregnation Time ◽

Mechanical Strengths ◽

Autoclave Reactor

A series of metal oxides sorbents supported on γ-Al2O3 were directly prepared by subcritical water impregnation (SCWI) method using an autoclave reactor. The effects of active components, preparation pressure, temperature, and time on the desulfurization activity of sorbents in hot coal-based gases at mid-temperature were investigated. The samples were characterized by X-ray diffraction (XRD), nitrogen adsorption and atomic absorption spectrophotometer (AAS). The results showed that Mn-based sorbent loaded on γ-Al2O3 by SCWI presented a good desulfurization performance. The optimal preparation parameters of sorbent were the temperature of 350 °C, the pressure of 18.9 MPa, impregnation time of 30 min, the precursor solution concentration of 0.287 mol/L and the volume of 100 ml, respectively. The Mn/γ-Al2O3 sorbent prepared under the optimal conditions presented a good desulfurization precision and regeneration performance. After regeneration, the mechanical strengths of the sorbents were higher than that of raw support and the breakthrough time at the desulfurization efficiency of above 99% was not obviously decreased.

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