Simple solvothermal approach to highly nanostructured hematite thin films

<div>In this work, we present a solvothermal method for the synthesis of hematite thin films on fluorine-doped tin oxide</div><div>substrates. This simple method uses a precursor solution of iron(III) 2,4-pentanedionate dissolved in ethanol with a</div><div>microliter-scale amount of water and yields hematite ~ 500-nm thick films after annealing. The synthesised films</div><div>were characterised using an array of methods, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, diffuse reflectance, and powder x-ray diffraction. Incorporating water into the precursor solution provides nucleation sites for the reaction and results show that by altering the amount of water used in the synthesis, it is possible to generate nanocrystalline films of different morphologies, nanocrystal size distributions, and surface areas. This synthetic procedure therefore provides control over the films’ physical and electrochemical characteristics. Doping of hematite thin films is also possible using this synthesis, as exemplified by doping with tin by adding tin(II) 2,4-pentanedionate to the precursor solution. To demonstrate utility, we build prototype photoelectrochemical cells using the synthesized hemtatite as the photoanode.</div>

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Simple Solvothermal Approach to Highly Nanostructured Hematite Thin Films

10.26434/chemrxiv.12730787.v1 ◽

2020 ◽

Author(s):

Casey M. Platnich ◽

Jachym Slaby ◽

David O'Connell ◽

Simon Trudel

Keyword(s):

Thin Films ◽

Precursor Solution ◽

Photoelectrochemical Cells ◽

Electrochemical Characteristics ◽

X Ray Diffraction ◽

Simple Method ◽

X Ray ◽

Surface Areas ◽

Nucleation Sites ◽

Synthetic Procedure

<div>In this work, we present a solvothermal method for the synthesis of hematite thin films on fluorine-doped tin oxide</div><div>substrates. This simple method uses a precursor solution of iron(III) 2,4-pentanedionate dissolved in ethanol with a</div><div>microliter-scale amount of water and yields hematite ~ 500-nm thick films after annealing. The synthesised films</div><div>were characterised using an array of methods, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, diffuse reflectance, and powder x-ray diffraction. Incorporating water into the precursor solution provides nucleation sites for the reaction and results show that by altering the amount of water used in the synthesis, it is possible to generate nanocrystalline films of different morphologies, nanocrystal size distributions, and surface areas. This synthetic procedure therefore provides control over the films’ physical and electrochemical characteristics. Doping of hematite thin films is also possible using this synthesis, as exemplified by doping with tin by adding tin(II) 2,4-pentanedionate to the precursor solution. To demonstrate utility, we build prototype photoelectrochemical cells using the synthesized hemtatite as the photoanode.</div>

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ITO Thin Films on Silicon Buffer by Sol Gel Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.514-516.1155 ◽

2006 ◽

Vol 514-516 ◽

pp. 1155-1160 ◽

Cited By ~ 1

Author(s):

Talaat Moussa Hammad

Keyword(s):

Thin Films ◽

Indium Tin Oxide ◽

Optical Transmission ◽

Sol Gel ◽

Precursor Solution ◽

Charge Carriers ◽

X Ray Diffraction ◽

X Ray ◽

Ito Thin Films ◽

Uv Visible

Sol gel indium tin oxide thin films (In: Sn = 90:10) were prepared by the sol-gel dipcoating process on silicon buffer substrate. The precursor solution was prepared by mixing SnCl2.2H2O and InCl3 dissolved in ethanol and acetic acid. The crystalline structure and grain orientation of ITO films were determined by X-ray diffraction. The surface morphology of the films was characterized by scanning electron microscope (SEM). Optical transmission and reflectance spectra of the films were analyzed by using a UV-visible spectrophotometer. The transport properties of majority charge carriers for these films were studied by Hall measurement. ITO thin film with electrical resistivity of 7.6 ×10-3 3.cm, Hall mobility of approximately 2 cm2(Vs)-1 and free carrier concentration of approximately 4.2 ×1020 cm-3 are obtained for films 100 nm thick films. The I-V curve measurement showed typical I-V characteristic behavior of sol gel ITO thin films.

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Layer-by-Layer Self-Assembled Ferrite Multilayer Nanofilms for Microwave Absorption

Journal of Nanomaterials ◽

10.1155/2015/164619 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Jiwoong Heo ◽

Daheui Choi ◽

Jinkee Hong

Keyword(s):

Electron Microscopy ◽

Self Assembly ◽

Precursor Solution ◽

Ferrite Nanoparticles ◽

Energy Dispersive ◽

Layer By Layer ◽

X Ray Diffraction ◽

Simple Method ◽

X Ray ◽

Scanning Electron

We demonstrate a simple method for fabricating multilayer thin films containing ferrite (Co0.5Zn0.5Fe2O4) nanoparticles, using layer-by-layer (LbL) self-assembly. These films have microwave absorbing properties for possible radar absorbing and stealth applications. To demonstrate incorporation of inorganic ferrite nanoparticles into an electrostatic-interaction-based LbL self-assembly, we fabricated two types of films: (1) a blended three-component LbL film consisting of a sequential poly(acrylic acid)/oleic acid-ferrite blend layer and a poly(allylamine hydrochloride) layer and (2) a tetralayer LbL film consisting of sequential poly(diallyldimethylammonium chloride), poly(sodium-4-sulfonate), bPEI-ferrite, and poly(sodium-4-sulfonate) layers. We compared surface morphologies, thicknesses, and packing density of the two types of ferrite multilayer film. Ferrite nanoparticles (Co0.5Zn0.5Fe2O4) were prepared via a coprecipitation method from an aqueous precursor solution. The structure and composition of the ferrite nanoparticles were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, transmission electron microscopy, and scanning electron microscopy. X-ray diffraction patterns of ferrite nanoparticles indicated a cubic spinel structure, and energy dispersive X-ray spectroscopy revealed their composition. Thickness growth and surface morphology were measured using a profilometer, atomic force microscope, and scanning electron microscope.

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Lead Titanate Thin Films Prepared by Metallorganic Chemical Vapor Deposion (MOCVD) on Sapphire, Pt, and RuOx Substrates

MRS Proceedings ◽

10.1557/proc-335-93 ◽

1993 ◽

Vol 335 ◽

Cited By ~ 1

Author(s):

Warren C. Hendricks ◽

Seshu B. Desu ◽

Chien H. Peng

Keyword(s):

Thin Films ◽

Ruthenium Oxide ◽

Chemical Vapor ◽

X Ray Diffraction ◽

Experimental Conditions ◽

X Ray ◽

Composition Control ◽

Oxide Substrates ◽

Temperature Deposition ◽

Titanium Ethoxide

AbstractTransparent and highly specular PbTiO3 thin films were deposited on sapphire, platinum and ruthenium oxide-coated silicon wafers by hot-wall metallorganic chemical vapor deposition (MOCVD). Lead bis-tetramethylheptadionate and titanium ethoxide were used as chemical precursors. Films were deposited over a range of experimental conditions. X-ray diffraction (XRD) was used to determine the phases present in the films; Scanning Electron Microscopy (SEM) was used to examine the surface morphology and Energy Dispersive Spectroscopy (EDS) was used to determine the composition. Optical spectra were obtained to confirm the highly dense and transparent nature of the films. The chemical stability of the ruthenium oxide substrates in the MOCVD environment as well as the existence of a high-temperature deposition regime for composition control are also discussed.

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Structural and Morphological Properties of HfxZr1-xO2 Thin Films Prepared by Pechini Route

Materials Science Forum ◽

10.4028/www.scientific.net/msf.644.113 ◽

2010 ◽

Vol 644 ◽

pp. 113-116

Author(s):

L.A. García-Cerda ◽

Bertha A. Puente Urbina ◽

M.A. Quevedo-López ◽

B.E. Gnade ◽

Leo A. Baldenegro-Perez ◽

...

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Annealing Temperature ◽

Precursor Solution ◽

Dip Coating ◽

Morphological Properties ◽

X Ray Diffraction ◽

X Ray ◽

Dip Coating Technique ◽

Scanning Electron

In this study, HfxZr1-xO2 (0 < x < 1) thin films were deposited on silicon wafers using a dip-coating technique and by using a precursor solution prepared by the Pechini route. The effects of annealing temperature on the structure and morphological properties of the proposed films were investigated. HfxZr1-xO2 thin films with 1, 3 and 5 layers were annealed in air for 2 h at 600 and 800 °C and the structural and morphological properties studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD results show that the films have monoclinic and tetragonal structure depending of the Hf and Zr concentration. SEM photographs show that all films consist of nanocrystalline grains with sizes in the range of 6 - 13 nm. The total film thickness is about 90 nm.

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Improvement of Sensing Performance of Impedancemetric C2H2 Sensor Using SmFeO3 Thin-Films Prepared by a Polymer Precursor Method

Sensors ◽

10.3390/s19040773 ◽

2019 ◽

Vol 19 (4) ◽

pp. 773 ◽

Cited By ~ 3

Author(s):

Tomohisa Tasaki ◽

Satoko Takase ◽

Youichi Shimizu

Keyword(s):

Thin Film ◽

Thin Films ◽

Photoelectron Spectroscopy ◽

Precursor Solution ◽

Particle Growth ◽

Polymer Precursor ◽

X Ray Diffraction ◽

X Ray ◽

Sensor Material ◽

Perovskite Type

A sensitive an impedancemetric acetylene (C2H2) gas sensor device could be fabricated by using perovskite-type SmFeO3 thin-film as a sensor material. The uniform SmFeO3 thin-films were prepared by spin-coating and focusing on the effects of polymer precursor solutions. The prepared precursors and thin-films were characterized by means of thermal analysis,　Fourier-transform infrared spectroscopy, ultraviolet–visible spectroscopy, X-ray diffraction analysis, scanning electron microscopy and X-ray photoelectron spectroscopy . It was found that particle growth and increase in homogeneity of the prepared thin-film could be accelerated by the addition of acetyl acetone (AcAc) as a coordination agent in the polymer precursor solution. Moreover, the highly crystallized thin-film-based sensor showed good response properties and stabilities to a low C2H2 concentration between 0.5 and 2.0 ppm.

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Effect of Deposition Time on Structural and Optical Properties of ZnO Thin Films Deposited by Spray Pyrolysis

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.397.81 ◽

2019 ◽

Vol 397 ◽

pp. 81-87 ◽

Cited By ~ 1

Author(s):

Farid Khediri ◽

Abdelkader Hafdallah ◽

Mouna Bouhelal

Keyword(s):

Thin Films ◽

Optical Properties ◽

Spray Pyrolysis ◽

Deposition Time ◽

Spray Pyrolysis Technique ◽

Precursor Solution ◽

Zno Thin Films ◽

X Ray Diffraction ◽

Structural And Optical Properties ◽

X Ray

In this work Zinc oxide thin films prepared by spray pyrolysis technique. A set of ZnO thin films were deposited with various deposition times, on glass substrate at 350 °C. The precursor solution is formed with zinc acetate in distilled methanol with 0.1 molarity. The deposition time was ranged from 2 to 8 min. The structural and optical properties of those films were examined by X-ray diffraction (XRD) and ultraviolet-visible spectrometer (UV). X-ray diffraction patterns of the ZnO thin films showed polycrystalline hexagonal wurtzite structure and the preferred orientation was along (002) plane when the grain size varied between 9.66 and 16.67nm. ZnO thin films were highly transparent in the visible with the maximum transmittance of 85% and the optical band gap was found between 3.25 and 3.28 eV.

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Thermal Studies of Au-Ti Thin Films Deposited on Oxide Substrates

MRS Proceedings ◽

10.1557/proc-260-935 ◽

1992 ◽

Vol 260 ◽

Author(s):

J. W. Strane ◽

S. W. Russell ◽

Jian Li ◽

J. W. Mayer

Keyword(s):

Thin Films ◽

Thermal Studies ◽

Film Surface ◽

Heat Treating ◽

X Ray Diffraction ◽

X Ray ◽

Oxide Substrates ◽

Oxide Phases ◽

Micron Diameter ◽

Oxide Substrate

ABSTRACTCo-evaporated Au-Ti thin films deposited onto sapphire and silicon dioxide substrates were thermally treated over a temperature range of 300–900°C in both vacuum and reactive amb ients. Vacuum annealing produced negligible reaction between the oxide substrate and film, the Au-Ti, however, reacted to form intermetallic compounds with little net elemental redistribution in the film. Heat treating in oxygen resulted in segregation of titanium to the surface where it formed both rutile and anatase structures. In addition, the high interfacial energy between the gold and the oxide phases led to the formation of large (5 micron diameter) gold particles on the film surface or voids at the titania-gold interface. Annealing in Ammomia produced an oxynitride surface in addition to the Ti-Au separation, Au particulate formation, and/or interfacial voiding already observed. The extent of surface degradation observed during these reactive ambient anneals varied with Ti concentration and temperature. The film did not react with SiO2 under any circumstances, however, at temperatures above 650°C in reactive ambients the titanium accumulated at the Al2,O3 interface. These results were obtained by RBS, X-ray diffraction, TEM and SEM.

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Electrical and optical properties of spin-coated SnO2 nanofilms

Materials Science-Poland ◽

10.2478/s13536-014-0265-2 ◽

2014 ◽

Vol 32 (4) ◽

pp. 729-736 ◽

Cited By ~ 3

Author(s):

Weronika Izydorczyk ◽

Krzysztof Waczyński ◽

Jacek Izydorczyk ◽

Paweł Karasiński ◽

Janusz Mazurkiewicz ◽

...

Keyword(s):

Thin Films ◽

Precursor Solution ◽

Silicon Substrates ◽

X Ray Diffraction ◽

Electrical And Optical Properties ◽

X Ray ◽

Different Temperatures ◽

Sno2 Thin Films ◽

Deposited Films ◽

Nanocrystalline Thin Films

AbstractSnO2 nanocrystalline thin films have been deposited on oxidized silicon substrates by spin-coating from a precursor solution, followed by slow thermal annealing in oxygen atmosphere at different temperatures (500 to 900 °C). The precursor solution consisted of 1.0 to 2.0 M SnCl4·5H2O in isopropanol. It was shown that the concentration of the precursor solution, annealing temperature and heating rate had a significant effect on the structural, optical and electrical properties of the studied thin films. The topography of SnO2 thin films was examined by scanning electron microscopy (SEM). Furthermore, as-deposited films were characterized by X-ray diffraction (XRD), UV-Vis and impedance spectroscopy.

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