Herein,a simple method for preparing poly(vinylidene fluoride)(PVDF)films with controlledβ/γratios by spin-coating assisted by potassium bromide(KBr)is proposed.The results show that the relative fraction of theβph...Herein,a simple method for preparing poly(vinylidene fluoride)(PVDF)films with controlledβ/γratios by spin-coating assisted by potassium bromide(KBr)is proposed.The results show that the relative fraction of theβphase(denoted as Fβ)for the films prepared on the KBr surface first decreased until a critical temperature(denoted as Tc)was reached,and then increased with increasing spin-coating temperature.This was related to the dissolved K and Br ions in the films.Further experiments showed that below Tc,high humidity can enhance Fβbut exhibit an adverse effect at and above Tc.The high content of K and Br ions in the PVDF/KBr blend film and larger shear stress can facilitate the formation of theβphase,leading exclusively to the formation ofβ-andγ-phases.The mechanism responsible for the change in Fβwith temperature was proposed:below Tc,the decrease in water intake with increasing temperature results in the decline of Fβ,whereas above Tc,the increase in Fβwith temperature is attributed to the synergistic effect of ions and shear stress.Ultimately,this paves the way for fabricating PVDF films with tailoredβ/γratios for electroactive and energy-harvesting applications.展开更多
La0.9Sr0.1Ga0.8Mg0.2O3-δ（LSGM） and La0.7Sr0.3Cr0.5Mn0.5O3-δ（LSCM） powders were synthesized by glycine-nitrate process, and LSGM electrolyte thin film was successfully fabricated on porous anode substrate of LSCM...La0.9Sr0.1Ga0.8Mg0.2O3-δ（LSGM） and La0.7Sr0.3Cr0.5Mn0.5O3-δ（LSCM） powders were synthesized by glycine-nitrate process, and LSGM electrolyte thin film was successfully fabricated on porous anode substrate of LSCM by slurry spin coating technology. Some technical parameters for the preparation of LSGM thin films were systematically investigated, including ink composition,sintering temperature, and spin coating times. The electrolyte films with the best compactness and somewhat rough are obtained when the operating parameters are fixed as follows: the content of ethyl cellulose as binder is 5 wt%, the content of terpineol as modifier is 5 wt%, the optimum coating cycle number is 9 times, and the best post-deposition sintering temperature is 1,400 °C for 4 h.展开更多
Lanthanide clusters [Ln4（μ3-OH）2（η2-accp）4（（μ-O）-η2-accp）6]（Ln = Y（4）,Gd（5）; accp = 2-acetylcyclopentanoate） are accessible by treatment of [M（NO33·6 H2 O]（M = Y（1）,Gd（2）） with 3 equiv. o...Lanthanide clusters [Ln4（μ3-OH）2（η2-accp）4（（μ-O）-η2-accp）6]（Ln = Y（4）,Gd（5）; accp = 2-acetylcyclopentanoate） are accessible by treatment of [M（NO33·6 H2 O]（M = Y（1）,Gd（2）） with 3 equiv. of Haccp（3） in presence of NaOH. The molecular structures of 4 and 5） in the solid-state are discussed. The thermal behavior of 4 and 5 was studied by TG under Ar and O2, showing multistep decomposition processes. Additionally, DSC studies were carried out under an atmosphere of O2. PXRD measurements of the TG residues confirm the formation of Ln2 O3.Spin-coating experiments were carried out with 4 and 5 for Ln2 O3 film deposition on silicon substrates. The layers are smooth, close and are of thicknesses of 18.87±1.13 nm and 25.59 ± 4.55 nm for Ln = Y and Gd, which was evidenced by SEM and EDX studies. Field-effect transistors were successfully fabricated by deposition of carbon nanotubes on top of the Y2 O3 films and formation of palladium contacts by a lift-off procedure. An on/off ratio of more than 4 orders of magnitude is achieved without considerable leakage currents. These results demonstrate the potential use of spin-coated Y2 O3 as a gate dielectric in electronic devices.展开更多
In this study,Tungsten Oxide(WO_3)thin films were prepared by Chemical Spray Pyrolysis(CSP)and Spin Coating(SC)techniques and it was investigated effects of technique and parameter on the films.WO_3 thin films were de...In this study,Tungsten Oxide(WO_3)thin films were prepared by Chemical Spray Pyrolysis(CSP)and Spin Coating(SC)techniques and it was investigated effects of technique and parameter on the films.WO_3 thin films were deposited on ITO(Indium Tin Oxide)coated glasses.The structural,optical and electrochromic properties of the WO_3 thin films were characterized by XRD,SEM,UV,and CV measurements.The sharpest(200)peak was observed in the XRD spectra and optical band gaps were calculated around 2.6～3.1 eVvia UV-Vis spectra for all of the samples.Micro fibrous reticulated surface(filamentous like)morphology for the films deposited by CSP technique and smooth surface morphology with high optical transmittance for the film deposited by SC Technique were obtained from SEM images.In addition to these results,it was revealed that all the samples exhibit good electrochromic performance.展开更多
In the present study, niobium-doped indium oxide thin films were prepared by sol-gel spin coating technique. The effects of different Nb-doping contents on structural, morphological, optical, and electrical properties...In the present study, niobium-doped indium oxide thin films were prepared by sol-gel spin coating technique. The effects of different Nb-doping contents on structural, morphological, optical, and electrical properties of the films were characterized by means of X-ray diffraction （XRD）, field emission scanning electron microscopy （FESEM）, atomic force microscopy （AFM）, UV-Vis spectroscopy, and four point probe methods. XRD analysis confirmed the formation of cubic bixbyite structure of In203 with a small shift in major peak position toward lower angles with addition of Nb. FESEM micrographs show that grain size decreased with increasing the Nb-doping content. Optical and electrical studies revealed that optimum opto-electronic properties, including minimum electrical resistivity of 119.4 × 10^-3 Ω cm and an average optical transmittance of 85% in the visible region with a band gap of 3.37 eV were achieved for the films doped with Nb-doping content of 3 at.%. AFM studies show that addition of Nb at optimum content leads to the formation of compact films with smooth surface and less average roughness compared with the prepared ln2O3 films.展开更多
In this work,we propose a new spin-coating method coupling with high thermal decomposition,to prepare the tin-antimony（Sn-Sb） oxide electrode.The character of the spin-coating electrode was compared with the dip-coa...In this work,we propose a new spin-coating method coupling with high thermal decomposition,to prepare the tin-antimony（Sn-Sb） oxide electrode.The character of the spin-coating electrode was compared with the dip-coating electrode through X-ray diffraction（XRD）,scanning electron microscopy（SEM）,accelerated life test,cyclic voltammetry,and electrolytic degradability. The results showed that the spin-coating electrode had a better defined crystal form,a smoother and more compact surface than that of the dip-coating electrode.Service time of the spin-coating electrode was determined to be longer than 15 h,and it was less than 2 min for the dip-coating electrode.Electrochemical characterization analysis showed that the electrolytic degradability of the spin-coating electrode is better than that of the dip-coating electrode.展开更多
This paper presented the preparation of TiO2 thin film on empty glass and Indium Tin Oxide (ITO) glass by spin coating method. Highly transparent titanium oxide thin films were obtained. The Optical absorption and tra...This paper presented the preparation of TiO2 thin film on empty glass and Indium Tin Oxide (ITO) glass by spin coating method. Highly transparent titanium oxide thin films were obtained. The Optical absorption and transmission of the film prepared from both the synthesized and the commercially available TiO2 were measured by the UV-Visible Spectrophotometer. A sharp absorption edge of the TiO2 film was observed. The estimated energy band gap for the film of the commercially available sample was larger than that of the synthesized one.展开更多
The effects of the spin coating process parameters on the thickness of the SiOx layer of the BOPP/SiOx composite film were investigated. When the concentration of tetraethoxysilane （TEOS） increased from 12.5 vol% to...The effects of the spin coating process parameters on the thickness of the SiOx layer of the BOPP/SiOx composite film were investigated. When the concentration of tetraethoxysilane （TEOS） increased from 12.5 vol% to 55% vol%, the SiOx thickness increased from about 80 nm to 470 nm. In the sol time range of 1.5 h to 5 h the SiOx layer thickness reached a maximum at about 4 h and the change of the thickness roughly matched the change of the silica colloidal sphere sizes in sol. When the spin-coating speed of the dispensing stage increased from 450 r/min to 500 r/min, the SiOx layer thickness drastically decreased from about 1.67 gm to 400 nm. While the spin-coating speed of the thinning and drying stage went up to 1200 r/min, the SiOx layer thickness was in the range of 330 nm to 390 nm. It was also found that the SiOx layer thickness was almost increased linearly from about 500 nm to 1.02 gm with the ratio of the commercial silica colloidal to the TEOS from 0.2 to 1.0. The water contact angles decreased to about 23.0° for the BOPP/Si-Sol composite film with 1.67 μm SiOx layer and about 4.0° for the BOPP/mixing Si-Sol composite film with 1.02 μm SiOx layer. Compared to BOPP, the light transparency of the BOPP/Si-Sol composite films decreased by about 5.5% with the SiOx layer from about 80 nm to 1.67 μm and by 7.0% for the BOPP/mixing Si-Sol composite film with the SiOx layer from about 350 nm to 1.02 μm respectively.展开更多
A new hybrid organic-inorganic structure of FTO/TiO2/Se/HTL/Au based selenium solar cell has been fabricated through a low-cost spin-coating process in air. In this process, selenium is completely dissolved in hydrazi...A new hybrid organic-inorganic structure of FTO/TiO2/Se/HTL/Au based selenium solar cell has been fabricated through a low-cost spin-coating process in air. In this process, selenium is completely dissolved in hydrazine, to fk）rm a homogeneous precursor solution. After spin-coating the precursor solution on the TiO2 substrates, following by sintering at 200 ℃ for 5rain, a uniform selenium film with crystalline grains is formed. The selenium based solar cell exhibits an efficiency of 1.23% under AM1.5 illumination （100 mW.cm-2）, short-circuit current density of 8 mA.cm 2, open-circuit voltage of 0.55 V, and fill factor of 0.37. Moreover, the device shows a stable ability with almost the same performance alter 60 days.展开更多
Scintillation light from a liquid noble gas during a neutrino or dark matter experiment lies typically within the vacuum ultraviolet region and might be strongly absorbed by surrounding materials such as light guides ...Scintillation light from a liquid noble gas during a neutrino or dark matter experiment lies typically within the vacuum ultraviolet region and might be strongly absorbed by surrounding materials such as light guides or photomultipliers.Tetraphenyl butadiene(TPB)is a fluorescent material,acts as a wavelength shifter,and can turn UV light into visible light at a peak wavelength of approximately 425 nm,enabling the light signals to be easily detected during physics studies.Compared with a traditional TPB coating method using vapor deposition,we propose an alternative technique applying a spin-coating procedure to facilitate the development of neutrino and dark matter detectors.This article introduces a method to fabricate a TPB film on an acrylic substrate by using a spincoating method,reports the measurements of the sample film thickness and roughness,demonstrates the reemission spectrum,and quantifies the wavelength shifting efficiency.展开更多
The polymer spin coating is critical in flexible electronic manufaction and micro-electro-mechanical system（MEMS）devices due to its simple operation, and uniformly coated layers. Some researchers focus on the effect...The polymer spin coating is critical in flexible electronic manufaction and micro-electro-mechanical system（MEMS）devices due to its simple operation, and uniformly coated layers. Some researchers focus on the effects of spin coating parameters such as wafer rotating speed, the viscosity of the coating liquid and solvent evaporation on final film thickness.In this work, the influence of substrate curvature on film thickness distribution is considered. A new parameter which represents the edge bead effect ratio（re） is proposed to investigate the influence factor of edge bead effect. Several operation parameters including the curvature of the substrate and the wafer-spin speed are taken into account to study the effects on the film thickness uniformity and edge-bead ratio. The morphologies and film thickness values of the spin-coated PDMS films under various substrate curvatures and coating speeds are measured with laser confocal microscopy. According to the results, both the convex and concave substrate will help to reduce the edge-bead effect significantly and thin film with better surface morphology can be obtained at high spin speed. Additionally, the relationship between the edge-bead ratio and the thin film thickness is like parabolic curve instead of linear dependence. This work may contribute to the mass production of flexible electronic devices.展开更多
Ca0.25Ba0.75Nb2O6 （CBN25） thin film was prepared on quartz substrate by spinning coating and the optical properties were investigated by a Hitachi U-3410 spectrophotometer and a Metricon 2010 prism coupler. The opti...Ca0.25Ba0.75Nb2O6 （CBN25） thin film was prepared on quartz substrate by spinning coating and the optical properties were investigated by a Hitachi U-3410 spectrophotometer and a Metricon 2010 prism coupler. The optical band gap, thickness and refractive index at 632.8 nm of the CBN25 thin film were determined to be 3.65 eV, 529 nm and 2.2258, respectively. The dispersion of the refractive index fitted to Sellmeier relation well and optical waves could be guided into the thin film, which implied that CBN25 thin films were promising for integrated optics and optically active devices.展开更多
ZnO thin films co-doped with A1 and Sb with different concentrations and a fixed molar ratio of AlCl3 to SbCl3 at 1：2, are prepared by a sol-gel spin-coating method on glass annealed at 550 ℃ for 2 h in air. The x-r...ZnO thin films co-doped with A1 and Sb with different concentrations and a fixed molar ratio of AlCl3 to SbCl3 at 1：2, are prepared by a sol-gel spin-coating method on glass annealed at 550 ℃ for 2 h in air. The x-ray diffraction results confirm that the ZnO thin films co-doped with Al distortion, and the biaxial stresses are 1.03× 10^8. 3.26× 10^8 and Sb are of wurtzite hexagonal ZnO with a very small 5.23 × 10^8, and 6.97× 10^8 Pa, corresponding to those of the ZnO thin films co-doped with Al and Sb in concentrations of 1.5, 3.0, 4.5, 6.0 at% respectively. The optical properties reveal that the ZnO thin films co-doped with Al and Sb have obviously enhanced transmittance in the visible region. The electrical properties show that ZnO thin film co-doped with Al and Sb in a concentration of 1.5 at% has a lowest resistivity of 2.5 Ω·cm.展开更多
This work investigated the electrical properties of TiO2 thin film on empty glass and ITO glass by spin coating method. Highly transparent titanium oxide thin films were prepared on empty glass and Indium Tin Oxide (I...This work investigated the electrical properties of TiO2 thin film on empty glass and ITO glass by spin coating method. Highly transparent titanium oxide thin films were prepared on empty glass and Indium Tin Oxide (ITO) from a titanium (III) chloride precursor. The sheet resistance of the film prepared from both the synthesised and the commercially available TiO2 was measured by the Keithley four-point probe tester (KFPPT). A comparable sheet resistance of 10.69E + 00 Ω/sq was obtained on the ITO. The electrical conductivity of the TiO2 film on ITO glass substrate was found to be very high (3.46E + 05 Ω-1?cm-1) and comparable to that of the bare ITO glass.展开更多
This work focuses on the sol-gel spin coating technique of TiO2 nanostructure synthesis and its characterization. Though various methods have been used to fabricate TiO2 nanostructure, much effort has not been exerted...This work focuses on the sol-gel spin coating technique of TiO2 nanostructure synthesis and its characterization. Though various methods have been used to fabricate TiO2 nanostructure, much effort has not been exerted to achieve better photoresponsive and narrowly dispersed TiO2 nanostructure using the sol-gel spin coating method. Therefore, it is imperative to realize the synthesis of TiO2 nanostructures, and investigate their properties. In this work, TiO2 is synthesized by sol-gel spin coating technique using titanium tetraisopropoxide, isopropanol, acetic acid and deionized water as starting materials and deposited on borosilicate glass substrates. The effects of annealing temperatures (300˚C, 400˚C and 500˚C) on the structural and optical properties of the films were investigated by different techniques: Scanning Electron Microscopy (SEM), optical microscopy and UV-visible spectrophotometry. The optical characterization showed the direct band gap at 3.7 eV, 3.6 eV and 3.4 eV for 300˚C, 400˚C and 500˚C, respectively, and the optical transmittance and reflectance spectra showed a greater performance at 500˚C. The grain sizes obtained from SEM annealed at 300˚C, 400˚C and 500˚C are found to be about 6.0 nm, 5.0 nm and 4.0 nm respectively. The grain size of TiO2 nanostructure films decreased with increasing annealing temperatures. The results clearly indicated that the sol-gel spin coating synthesis of TiO2 nanostructure and post-thermal treatment at 500˚C cooled naturally at room temperature result in better photoresponsive and narrowly dispersed TiO2 nanostructure films with higher photoresponsive and good optical properties.展开更多
Transparent zinc oxide（ZnO） thin films are fabricated by a simple sol-gel spin-coating technique on glass substrates with different solution concentrations（0.3-1.2 M） using zinc acetate dehydrate [Zn（CH_3COO）_2&...Transparent zinc oxide（ZnO） thin films are fabricated by a simple sol-gel spin-coating technique on glass substrates with different solution concentrations（0.3-1.2 M） using zinc acetate dehydrate [Zn（CH_3COO）_2·2H_2O] as precursor and isopropanol and monoethanolamine（MEA） as solvent and stabilizer, respectively. The molar ratio of zinc acetate dehydrate to MEA is 1.0. X-ray diffraction, ultraviolet-visible spectroscopy and photoluminescence spectroscopy are employed to investigate the effect of solution concentration on the structural and optical properties of the ZnO thin films. The obtained results of all thin films are discussed in detail and are compared with other experimental data.展开更多
This paper reports the synthesis and characterization of ZnO thin films prepared by sol-gel spin coating technique. The sol-gel was prepared from zinc acetate dehydrate as a precursor, 2-me- thoxyethanol as a solvent ...This paper reports the synthesis and characterization of ZnO thin films prepared by sol-gel spin coating technique. The sol-gel was prepared from zinc acetate dehydrate as a precursor, 2-me- thoxyethanol as a solvent and di-ethanolamine as a stabilizer, and then deposited on glass substrate using spin coater at the coating speed of 1000 rpm, 2000 rpm, 3000 rpm, 4000 rpm, 5000 rpm and 6000 rpm. After pre-heated at 150℃, the samples were post-heated at 250oC and also annealed at 400℃. X-ray diffraction (XRD) of the films showed polycrystalline hexagonal structure, with (002) orientation as most intense peak having a grain size of 28.1 nm. The absorbance of the film decreases with increasing wavelength and the transmittance was generally high between visible regions from 280 nm - 1200 nm. The ZnO films deposited at a spinning speed of 2000 rpm had highest transmittance of 88% in the visible region from 280 nm - 1200 nm. The energy band gap was found to be in the range of 3.23 - 3.40 eV. The thicknesses of the films decreased with increase in coating speed. Based on these results, ZnO thin films obtained could have useful application in transparent conducting oxide electrode in solar cells.展开更多
A new nanometer-scale ferrite thin film with excellent high-frequency characteristics has been developed by the spray-spin-heating-coating method. The effects of the ion synthesis mechanism, chemical stoichiometry, fa...A new nanometer-scale ferrite thin film with excellent high-frequency characteristics has been developed by the spray-spin-heating-coating method. The effects of the ion synthesis mechanism, chemical stoichiometry, fabrication method, and doping content on the magnetic properties and microstructure of the thin films have been analyzed. The films formed between 75℃ and 90℃ by spray-spin-heating-coating methods was discovered with fine grain size of about 21 nm, high saturation magnetization (4πMs) of about 6.5 kGs, coercivity of about 9.8 Oe, as well as initial permeability of about 14.0. These films can be widely used in radio-frequency integrated circuit devices.展开更多
This paper is concerned with the improvement of dye-sensitized solar cell (DSSC) efficiency upon ZnO-coating of the TiO2 electrode. Sol-gel ZnO of controlled amount by varying the number of sol drops during spin-coati...This paper is concerned with the improvement of dye-sensitized solar cell (DSSC) efficiency upon ZnO-coating of the TiO2 electrode. Sol-gel ZnO of controlled amount by varying the number of sol drops during spin-coating is shown to increase the DSSC efficiency. The highest efficiency is obtained at a single sol drop with enhancement of 40%, while beyond this amount the efficiency falls down sharply to zero. Based on measured optical absorption spectra of the different dye-loaded electrodes, it is concluded that this amount of ZnO sol corresponds to the thinnest layer that can create the energy barrier to minimize the electron recombination rate without seriously affecting the dye adsorption efficiency of the TiO2 film.展开更多
基金support from the National Natural Science Foundation of China(Nos.52203026 and 52027804)。
文摘Herein,a simple method for preparing poly(vinylidene fluoride)(PVDF)films with controlledβ/γratios by spin-coating assisted by potassium bromide(KBr)is proposed.The results show that the relative fraction of theβphase(denoted as Fβ)for the films prepared on the KBr surface first decreased until a critical temperature(denoted as Tc)was reached,and then increased with increasing spin-coating temperature.This was related to the dissolved K and Br ions in the films.Further experiments showed that below Tc,high humidity can enhance Fβbut exhibit an adverse effect at and above Tc.The high content of K and Br ions in the PVDF/KBr blend film and larger shear stress can facilitate the formation of theβphase,leading exclusively to the formation ofβ-andγ-phases.The mechanism responsible for the change in Fβwith temperature was proposed:below Tc,the decrease in water intake with increasing temperature results in the decline of Fβ,whereas above Tc,the increase in Fβwith temperature is attributed to the synergistic effect of ions and shear stress.Ultimately,this paves the way for fabricating PVDF films with tailoredβ/γratios for electroactive and energy-harvesting applications.
基金financially supported by the National Natural Science Foundation of China (Nos. 51362011 and 51362012)the Chemistry Discipline Master’s Site Construction Open Foundation of Honghe University of Yunnan Province (No. HXZ1308)
文摘La0.9Sr0.1Ga0.8Mg0.2O3-δ（LSGM） and La0.7Sr0.3Cr0.5Mn0.5O3-δ（LSCM） powders were synthesized by glycine-nitrate process, and LSGM electrolyte thin film was successfully fabricated on porous anode substrate of LSCM by slurry spin coating technology. Some technical parameters for the preparation of LSGM thin films were systematically investigated, including ink composition,sintering temperature, and spin coating times. The electrolyte films with the best compactness and somewhat rough are obtained when the operating parameters are fixed as follows: the content of ethyl cellulose as binder is 5 wt%, the content of terpineol as modifier is 5 wt%, the optimum coating cycle number is 9 times, and the best post-deposition sintering temperature is 1,400 °C for 4 h.
基金Project supported by the German Research Foundation(Cluster of Excellence Center for Advancing Electronics Dresden(cfaed))
文摘Lanthanide clusters [Ln4（μ3-OH）2（η2-accp）4（（μ-O）-η2-accp）6]（Ln = Y（4）,Gd（5）; accp = 2-acetylcyclopentanoate） are accessible by treatment of [M（NO33·6 H2 O]（M = Y（1）,Gd（2）） with 3 equiv. of Haccp（3） in presence of NaOH. The molecular structures of 4 and 5） in the solid-state are discussed. The thermal behavior of 4 and 5 was studied by TG under Ar and O2, showing multistep decomposition processes. Additionally, DSC studies were carried out under an atmosphere of O2. PXRD measurements of the TG residues confirm the formation of Ln2 O3.Spin-coating experiments were carried out with 4 and 5 for Ln2 O3 film deposition on silicon substrates. The layers are smooth, close and are of thicknesses of 18.87±1.13 nm and 25.59 ± 4.55 nm for Ln = Y and Gd, which was evidenced by SEM and EDX studies. Field-effect transistors were successfully fabricated by deposition of carbon nanotubes on top of the Y2 O3 films and formation of palladium contacts by a lift-off procedure. An on/off ratio of more than 4 orders of magnitude is achieved without considerable leakage currents. These results demonstrate the potential use of spin-coated Y2 O3 as a gate dielectric in electronic devices.
基金supported by Erzincan University Scientific Research Project(Project No:09.02.01)and Tübitak-Bideb National Scholarship Program for PhD S tudent
文摘In this study,Tungsten Oxide(WO_3)thin films were prepared by Chemical Spray Pyrolysis(CSP)and Spin Coating(SC)techniques and it was investigated effects of technique and parameter on the films.WO_3 thin films were deposited on ITO(Indium Tin Oxide)coated glasses.The structural,optical and electrochromic properties of the WO_3 thin films were characterized by XRD,SEM,UV,and CV measurements.The sharpest(200)peak was observed in the XRD spectra and optical band gaps were calculated around 2.6～3.1 eVvia UV-Vis spectra for all of the samples.Micro fibrous reticulated surface(filamentous like)morphology for the films deposited by CSP technique and smooth surface morphology with high optical transmittance for the film deposited by SC Technique were obtained from SEM images.In addition to these results,it was revealed that all the samples exhibit good electrochromic performance.
基金Iran Initiative Nanotechnology Council for partially supporting this workMahar Fan Abzar Co.for AFM spectroscopy results
文摘In the present study, niobium-doped indium oxide thin films were prepared by sol-gel spin coating technique. The effects of different Nb-doping contents on structural, morphological, optical, and electrical properties of the films were characterized by means of X-ray diffraction （XRD）, field emission scanning electron microscopy （FESEM）, atomic force microscopy （AFM）, UV-Vis spectroscopy, and four point probe methods. XRD analysis confirmed the formation of cubic bixbyite structure of In203 with a small shift in major peak position toward lower angles with addition of Nb. FESEM micrographs show that grain size decreased with increasing the Nb-doping content. Optical and electrical studies revealed that optimum opto-electronic properties, including minimum electrical resistivity of 119.4 × 10^-3 Ω cm and an average optical transmittance of 85% in the visible region with a band gap of 3.37 eV were achieved for the films doped with Nb-doping content of 3 at.%. AFM studies show that addition of Nb at optimum content leads to the formation of compact films with smooth surface and less average roughness compared with the prepared ln2O3 films.
基金the financial support from the Program for New Century Excellent Talents in University(NoNCET-07-0683)President Research Fund of Xi'an Jiaotong University(No08140016)
文摘In this work,we propose a new spin-coating method coupling with high thermal decomposition,to prepare the tin-antimony（Sn-Sb） oxide electrode.The character of the spin-coating electrode was compared with the dip-coating electrode through X-ray diffraction（XRD）,scanning electron microscopy（SEM）,accelerated life test,cyclic voltammetry,and electrolytic degradability. The results showed that the spin-coating electrode had a better defined crystal form,a smoother and more compact surface than that of the dip-coating electrode.Service time of the spin-coating electrode was determined to be longer than 15 h,and it was less than 2 min for the dip-coating electrode.Electrochemical characterization analysis showed that the electrolytic degradability of the spin-coating electrode is better than that of the dip-coating electrode.
文摘This paper presented the preparation of TiO2 thin film on empty glass and Indium Tin Oxide (ITO) glass by spin coating method. Highly transparent titanium oxide thin films were obtained. The Optical absorption and transmission of the film prepared from both the synthesized and the commercially available TiO2 were measured by the UV-Visible Spectrophotometer. A sharp absorption edge of the TiO2 film was observed. The estimated energy band gap for the film of the commercially available sample was larger than that of the synthesized one.
基金financially supported by the Chinese Universities Scientific Fund (ZD0902)
文摘The effects of the spin coating process parameters on the thickness of the SiOx layer of the BOPP/SiOx composite film were investigated. When the concentration of tetraethoxysilane （TEOS） increased from 12.5 vol% to 55% vol%, the SiOx thickness increased from about 80 nm to 470 nm. In the sol time range of 1.5 h to 5 h the SiOx layer thickness reached a maximum at about 4 h and the change of the thickness roughly matched the change of the silica colloidal sphere sizes in sol. When the spin-coating speed of the dispensing stage increased from 450 r/min to 500 r/min, the SiOx layer thickness drastically decreased from about 1.67 gm to 400 nm. While the spin-coating speed of the thinning and drying stage went up to 1200 r/min, the SiOx layer thickness was in the range of 330 nm to 390 nm. It was also found that the SiOx layer thickness was almost increased linearly from about 500 nm to 1.02 gm with the ratio of the commercial silica colloidal to the TEOS from 0.2 to 1.0. The water contact angles decreased to about 23.0° for the BOPP/Si-Sol composite film with 1.67 μm SiOx layer and about 4.0° for the BOPP/mixing Si-Sol composite film with 1.02 μm SiOx layer. Compared to BOPP, the light transparency of the BOPP/Si-Sol composite films decreased by about 5.5% with the SiOx layer from about 80 nm to 1.67 μm and by 7.0% for the BOPP/mixing Si-Sol composite film with the SiOx layer from about 350 nm to 1.02 μm respectively.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51579057,5177090655,and 51379052)the State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,China(Grant No.2016DX07)
文摘A new hybrid organic-inorganic structure of FTO/TiO2/Se/HTL/Au based selenium solar cell has been fabricated through a low-cost spin-coating process in air. In this process, selenium is completely dissolved in hydrazine, to fk）rm a homogeneous precursor solution. After spin-coating the precursor solution on the TiO2 substrates, following by sintering at 200 ℃ for 5rain, a uniform selenium film with crystalline grains is formed. The selenium based solar cell exhibits an efficiency of 1.23% under AM1.5 illumination （100 mW.cm-2）, short-circuit current density of 8 mA.cm 2, open-circuit voltage of 0.55 V, and fill factor of 0.37. Moreover, the device shows a stable ability with almost the same performance alter 60 days.
基金supported in part by the Guangdong Basic and Applied Basic Research Foundation(No.2019A1515012216)the National Natural Science Foundation of China(No.11505301)the Innovation Training Program for bachelor students at the School of Physics in SYSU
文摘Scintillation light from a liquid noble gas during a neutrino or dark matter experiment lies typically within the vacuum ultraviolet region and might be strongly absorbed by surrounding materials such as light guides or photomultipliers.Tetraphenyl butadiene(TPB)is a fluorescent material,acts as a wavelength shifter,and can turn UV light into visible light at a peak wavelength of approximately 425 nm,enabling the light signals to be easily detected during physics studies.Compared with a traditional TPB coating method using vapor deposition,we propose an alternative technique applying a spin-coating procedure to facilitate the development of neutrino and dark matter detectors.This article introduces a method to fabricate a TPB film on an acrylic substrate by using a spincoating method,reports the measurements of the sample film thickness and roughness,demonstrates the reemission spectrum,and quantifies the wavelength shifting efficiency.
基金supported by the National Natural Science Foundation of China(Grant Nos.51605079 and 51475076)the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(Grant No.51621064)the China Postdoctoral Science Foundation(Grant No.2016M591424)
文摘The polymer spin coating is critical in flexible electronic manufaction and micro-electro-mechanical system（MEMS）devices due to its simple operation, and uniformly coated layers. Some researchers focus on the effects of spin coating parameters such as wafer rotating speed, the viscosity of the coating liquid and solvent evaporation on final film thickness.In this work, the influence of substrate curvature on film thickness distribution is considered. A new parameter which represents the edge bead effect ratio（re） is proposed to investigate the influence factor of edge bead effect. Several operation parameters including the curvature of the substrate and the wafer-spin speed are taken into account to study the effects on the film thickness uniformity and edge-bead ratio. The morphologies and film thickness values of the spin-coated PDMS films under various substrate curvatures and coating speeds are measured with laser confocal microscopy. According to the results, both the convex and concave substrate will help to reduce the edge-bead effect significantly and thin film with better surface morphology can be obtained at high spin speed. Additionally, the relationship between the edge-bead ratio and the thin film thickness is like parabolic curve instead of linear dependence. This work may contribute to the mass production of flexible electronic devices.
基金supported by the Fundamental Research Funds for the Central Universities (2010LKWL06)
文摘Ca0.25Ba0.75Nb2O6 （CBN25） thin film was prepared on quartz substrate by spinning coating and the optical properties were investigated by a Hitachi U-3410 spectrophotometer and a Metricon 2010 prism coupler. The optical band gap, thickness and refractive index at 632.8 nm of the CBN25 thin film were determined to be 3.65 eV, 529 nm and 2.2258, respectively. The dispersion of the refractive index fitted to Sellmeier relation well and optical waves could be guided into the thin film, which implied that CBN25 thin films were promising for integrated optics and optically active devices.
基金Project supported by the Innovation Foundation of Beijing University of Aeronautics and Astronautics for PhD Graduates, China (Grant No. 292122)the Equipment Research Foundation of China (Grant No. 373974)
文摘ZnO thin films co-doped with A1 and Sb with different concentrations and a fixed molar ratio of AlCl3 to SbCl3 at 1：2, are prepared by a sol-gel spin-coating method on glass annealed at 550 ℃ for 2 h in air. The x-ray diffraction results confirm that the ZnO thin films co-doped with Al distortion, and the biaxial stresses are 1.03× 10^8. 3.26× 10^8 and Sb are of wurtzite hexagonal ZnO with a very small 5.23 × 10^8, and 6.97× 10^8 Pa, corresponding to those of the ZnO thin films co-doped with Al and Sb in concentrations of 1.5, 3.0, 4.5, 6.0 at% respectively. The optical properties reveal that the ZnO thin films co-doped with Al and Sb have obviously enhanced transmittance in the visible region. The electrical properties show that ZnO thin film co-doped with Al and Sb in a concentration of 1.5 at% has a lowest resistivity of 2.5 Ω·cm.
文摘This work investigated the electrical properties of TiO2 thin film on empty glass and ITO glass by spin coating method. Highly transparent titanium oxide thin films were prepared on empty glass and Indium Tin Oxide (ITO) from a titanium (III) chloride precursor. The sheet resistance of the film prepared from both the synthesised and the commercially available TiO2 was measured by the Keithley four-point probe tester (KFPPT). A comparable sheet resistance of 10.69E + 00 Ω/sq was obtained on the ITO. The electrical conductivity of the TiO2 film on ITO glass substrate was found to be very high (3.46E + 05 Ω-1?cm-1) and comparable to that of the bare ITO glass.
文摘This work focuses on the sol-gel spin coating technique of TiO2 nanostructure synthesis and its characterization. Though various methods have been used to fabricate TiO2 nanostructure, much effort has not been exerted to achieve better photoresponsive and narrowly dispersed TiO2 nanostructure using the sol-gel spin coating method. Therefore, it is imperative to realize the synthesis of TiO2 nanostructures, and investigate their properties. In this work, TiO2 is synthesized by sol-gel spin coating technique using titanium tetraisopropoxide, isopropanol, acetic acid and deionized water as starting materials and deposited on borosilicate glass substrates. The effects of annealing temperatures (300˚C, 400˚C and 500˚C) on the structural and optical properties of the films were investigated by different techniques: Scanning Electron Microscopy (SEM), optical microscopy and UV-visible spectrophotometry. The optical characterization showed the direct band gap at 3.7 eV, 3.6 eV and 3.4 eV for 300˚C, 400˚C and 500˚C, respectively, and the optical transmittance and reflectance spectra showed a greater performance at 500˚C. The grain sizes obtained from SEM annealed at 300˚C, 400˚C and 500˚C are found to be about 6.0 nm, 5.0 nm and 4.0 nm respectively. The grain size of TiO2 nanostructure films decreased with increasing annealing temperatures. The results clearly indicated that the sol-gel spin coating synthesis of TiO2 nanostructure and post-thermal treatment at 500˚C cooled naturally at room temperature result in better photoresponsive and narrowly dispersed TiO2 nanostructure films with higher photoresponsive and good optical properties.
文摘Transparent zinc oxide（ZnO） thin films are fabricated by a simple sol-gel spin-coating technique on glass substrates with different solution concentrations（0.3-1.2 M） using zinc acetate dehydrate [Zn（CH_3COO）_2·2H_2O] as precursor and isopropanol and monoethanolamine（MEA） as solvent and stabilizer, respectively. The molar ratio of zinc acetate dehydrate to MEA is 1.0. X-ray diffraction, ultraviolet-visible spectroscopy and photoluminescence spectroscopy are employed to investigate the effect of solution concentration on the structural and optical properties of the ZnO thin films. The obtained results of all thin films are discussed in detail and are compared with other experimental data.
文摘This paper reports the synthesis and characterization of ZnO thin films prepared by sol-gel spin coating technique. The sol-gel was prepared from zinc acetate dehydrate as a precursor, 2-me- thoxyethanol as a solvent and di-ethanolamine as a stabilizer, and then deposited on glass substrate using spin coater at the coating speed of 1000 rpm, 2000 rpm, 3000 rpm, 4000 rpm, 5000 rpm and 6000 rpm. After pre-heated at 150℃, the samples were post-heated at 250oC and also annealed at 400℃. X-ray diffraction (XRD) of the films showed polycrystalline hexagonal structure, with (002) orientation as most intense peak having a grain size of 28.1 nm. The absorbance of the film decreases with increasing wavelength and the transmittance was generally high between visible regions from 280 nm - 1200 nm. The ZnO films deposited at a spinning speed of 2000 rpm had highest transmittance of 88% in the visible region from 280 nm - 1200 nm. The energy band gap was found to be in the range of 3.23 - 3.40 eV. The thicknesses of the films decreased with increase in coating speed. Based on these results, ZnO thin films obtained could have useful application in transparent conducting oxide electrode in solar cells.
基金supported by the National Natural Science Foundation of China under grant No.69671021.
文摘A new nanometer-scale ferrite thin film with excellent high-frequency characteristics has been developed by the spray-spin-heating-coating method. The effects of the ion synthesis mechanism, chemical stoichiometry, fabrication method, and doping content on the magnetic properties and microstructure of the thin films have been analyzed. The films formed between 75℃ and 90℃ by spray-spin-heating-coating methods was discovered with fine grain size of about 21 nm, high saturation magnetization (4πMs) of about 6.5 kGs, coercivity of about 9.8 Oe, as well as initial permeability of about 14.0. These films can be widely used in radio-frequency integrated circuit devices.
文摘This paper is concerned with the improvement of dye-sensitized solar cell (DSSC) efficiency upon ZnO-coating of the TiO2 electrode. Sol-gel ZnO of controlled amount by varying the number of sol drops during spin-coating is shown to increase the DSSC efficiency. The highest efficiency is obtained at a single sol drop with enhancement of 40%, while beyond this amount the efficiency falls down sharply to zero. Based on measured optical absorption spectra of the different dye-loaded electrodes, it is concluded that this amount of ZnO sol corresponds to the thinnest layer that can create the energy barrier to minimize the electron recombination rate without seriously affecting the dye adsorption efficiency of the TiO2 film.
