APPLIED OPTICS
·
2024
·Vol. 63
·期 10
·A70
·
IF 1.7
FengHong Chu,Dan Pei,ZhengLan Bian,YiSheng Sun,AnDuo Hu,GuiLin Zhang,Liang Xue,JiaWen Han,JiaMeng Zhang
Tungsten oxide (${{\rm WO}_3}$) has been widely used in hydrogen sensing due to its stable chemical properties and high oxygen vacancy diffusion coefficient. However, the response of pure ${{\rm WO}_3}$ to hydrogen is slow, and doping is an effective way to improve the hydrogen sensing performance of ${{\rm WO}_3}$ materials. In this paper, ${{\rm WO}_3}/{\rm Pt}/{\rm PEG}/{{\rm SiO}_2}$ porous film was prepared by the sol-gel method using tungsten powder, ${{\rm H}_2}{{\rm O}_2}$ and ${{\rm C}_2}{{\rm H}_5}{\rm OH}$ as precursors, polyethylene glycol (PEG) as the pore-forming agent, and tetraethyl orthosilicate (TEOS) as the ${{\rm SiO}_2}$ source material. The sensing properties of the ${{\rm WO}_3}$ composite for hydrogen were characterized by a transmission optical fiber hydrogen sensing system made at home. The process parameters such as water bath time, aging time, W:PEG ratio, and W:TEOS ratio were optimized to improve the sensitivity and response time of the sensing film. The experimental results indicate that the sensitivity is 15.68%, the average response time is 45 s, and the repeatability is up to 98.74% in 16 consecutive tests. The linearity index ${{\rm R}^2}$ is 0.9946 within the hydrogen concentration range of 5000 ppm to 50,000 ppm. The film responds only to ${{\rm H}_2}$ when the concentration of interfering gases (${{\rm CH}_4}$, CO, ${{\rm CO}_2}$) is 2000 ppm. The hydrogen sensing performance of the optimized film is significantly improved compared with that of the undoped film.
研究领域:
材料科学
·
传感器技术
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DOI
PubMed
高影响因子
Coatings
·
2023
·Vol. 13
·期 6
·1085
·
IF 3.4
Zhenchuan Lu,Kamale Tuokedaerhan,Haotian Cai,Hongguo Du,Renjia Zhang
This article presents the sol-gel method for depositing La2O3thin films on n-type Si substrates and quartz substrates, and investigates the impact of annealing temperature on the microcomposition, surface morphology, optical properties, and band characteristics of the films. X-ray diffraction (XRD) analysis indicates that the films are amorphous below 500 °C, with annealing resulting in a hexagonal-phase La2O3(h-a2O3) and new non-hydrated impurities. Fourier-transform infrared (FTIR) analysis reveals that the prepared La2O3film is unaffected by moisture. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) provide evidence that the La2O3film has a smooth, uniform surface without cracks. The roughness increases from 0.426 nm to 1.200 nm, and the film thins from 54.85 nm to 49.80 nm as the annealing temperature rises. The film’s transmittance is above 75%, as measured by UV-Vis, and the calculated optical bandgap increases from 5.11 eV to 5.75 eV. The calculated band offset of the La2O3film is greater than 1 eV, which meets the minimum requirements for MOS devices, thus providing promising prospects for La2O3films in MOS applications.Keywords:high k gate dielectric;sol-gel;La2O3;thin film
研究领域:
材料科学
·
半导体物理
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产品关联
DOI
高影响因子
Batteries-Basel
·
2025
·Vol. 11
·期 4
·142
·
IF 4.8
Pengqing Hou,Qi Sun,Shengxue Yan,Guanglong Li,Yingdong Qu,Shaohua Luo
The development of a simple and reliable strategy to synthesize cathode materials is crucial for achieving the overall high performance of rechargeable lithium batteries, which has proved to be quite challenging. Herein, we report a simple sol–gel method for the synthesis of Li2FeTiO4cathode materials. The reaction mechanism of Li2FeTiO4crystals can be divided into five stages: including the breakage of the coordination bond; the thermal decomposition of citric acid; the thermal decomposition of metal salts and the reduction of trivalent iron and the formation of Li2FeTiO4crystals. Finally, the optimum calcination temperature for the preparation of Li2FeTiO4cathode materials was explored. The Li2FeTiO4cathode material prepared at 700 °C provides a discharge-specific capacity of 121.3 mAh/g in the first cycle and capacity retention of 89.2%. Our results provide new insights into the application of Li2FeTiO4cathode materials.
研究领域:
材料科学
·
电化学
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产品关联
DOI
高影响因子
Materials
·
2018
·Vol. 11
·期 3
·350
·
IF 2.467
Guangyuan Yang,Zhixiong Huang,Xu Wang,Bo Wang
The paper proposed a method to improve the anti-oxidation performance of carbon fibers (CF) at high temperature environment by coating silicon dioxide (SiO2) and silicon carbide (SiC). The modified sol-gel method had been used to ensure the proper interface between fibers and coating. We used polydimethylsiloxane and ethyl orthosilicate to make stable emulsion to uniformly disperse SiC nanoparticles. The modified SiO2/SiC coating had been coated on CF successfully. Compared with the untreated CF, the coated fibers started to be oxidized around 900 °C and the residual weight was 57% at 1400 °C. The oxidation mechanism had been discussed. The structure of SiC/SiO2coated CF had been characterized by scanning electron microscope and X-ray diffraction analysis. Thermal gravimetric analysis was used to test the anti-oxidation ability of CF with different coatings.Keywords:carbon fiber;oxidation resistance;coating;characterization
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2013
·Vol. 13
·期 10
·6953-6960
·
IF 1.149
Shi Haowei,Huang Yan,Cheng Chao,Ji Guoyuan,Yang Yuxiang,Yuan Hongming
The size- and shape-controlled Fe3O4@SiO2 nanocomposites were successfully synthesized via the sol–gel method. The results showed that the size, shape, and property of the products were directly influenced by the amount of TEOS, and the concentration
of water-based magnetic fluid in the coating process. The morphology and properties of the products were characterized by TEM, SEM, X-ray powder diffraction, IR and EDS. The Fe3O4@SiO2 composites with easily-controlled size arranged from 58 to 835 nm could
be synthesized by adjusting the experimental parameters. When TEOS amount is 1 mL and the concentration of magnetic fluid were 30.0 and 10.0 mg/mL respectively, chain-like and peanuts-like well-dispersed Fe3O4@SiO2 particles with clear core–shell structure
were obtained. These size- and shape-controlled Fe3O4@SiO2 composites may have potential application in the field of targeted drug delivery and MRI contrast agent.
研究领域:
材料科学
·
纳米医学
✓ 已验证
DOI
PubMed
高影响因子
CLAYS AND CLAY MINERALS
·
2024
·Vol. 66
·期 5
·466-473
·
IF 2
Jingyi Liu,Rui Chen,Yuru Li,Jiajia Chen,Lihui Chen,Jing Gao,Guohua Li
The elimination of Pb2+ and recovery of lead metal during the treatment of industrial sewage is an important research topic. Montmorillonite (Mnt) is a promising material in this regard. The purpose of the present study was to improve the Pb2+ adsorption ability of Na-containing Mnt (Na-Mnt) by pillaring titania (anatase) into its interlayer spaces using a sol-gel method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The ratio of Ti to Mnt affected the crystal phase of titania-pillared Na-Mnt (Ti-Mnt), and changed the interlayer spacing of the (001) plane of Ti-Mnt and the growth of anatase. The Pb2+-adsorption capabilities of Ti-Mnt were tested using an aqueous solution of lead nitrate as a wastewater model. The Ti-Mnt prepared adsorbed >99.99% of the Pb2+; leached and activated Ti-Mnt adsorbed >95.7% of the Pb2+, indicating that Ti-Mnt could be recycled effectively. Furthermore, the Pb2+-adsorption capability of Ti- Mnt was related to the interlayer spacing of Mnt, the distribution of anatase particles pillared in Mnt, and the specific surface area, especially with respect to the relationship between the anatase particles and the interlayer spacing of the (001) plane.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
FIBERS AND POLYMERS
·
2018
·Vol. 19
·期 2
·340-349
·
IF 1.353
Wang Yixi,Wang Hao,Peng Huili,Wang Zhicun,Wu Jianning,Liu Zhiyong
A novel eco-friendly porous adsorbent of cellulose (CE)/chitosan (CS) aerogel was prepared through sol-gel process and freeze-drying to remove Congo Red (CR). A series of aerogels were prepared by adjusting the mass ratios of CE and CS. Composite aerogels were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). SEM images showed that it was possible to change the structure of the aerogel by adjusting the amount of chitosan. The effects of dosage of chitosan, initial pH, temperature, adsorbent dosage, contact time, and initial dye concentration on adsorption capacities for CR were studied in detail. Batch adsorption studies showed that aerogel exhibited maximum removal efficiency to CR at a composite ratio of 1:3 and dosage of 2.5 g/ l . CE/CS aerogel had excellent adsorption capacities for CR at a pH range of 3-11, which indicated stability of the aerogel in both acidic and alkaline conditions. CR adsorption on the composite aerogel fitted pseudo-second-order kinetics and Langmuir isotherm. The Langmuir isotherm model revealed that the maximum theoretical adsorption capacity of this material for CR was 381.7 mg/g at pH 7.0 at 303 K for 24 h. The adsorption mechanism included electrostatic and chemical interactions. The results indicated that the adsorption capacity of CE/CS aerogels was higher than the other chitosan composites adsorbents.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2022
·
IF 4.865
Linbo Zhang,Weihong Wan,Xianyu Jiang,Bo Wang,Liangjun Yin,Simeon Agathopoulos,Jiangliang Xie,Li Zhang,Haipeng Lu,Longjiang Deng
The popular magnetic material of flaky carbonyl iron (FCI) is unfortunately vulnerable to electrochemical corrosion when exposed to a salty and foggy environment. This work reports on a sol-gel method that successfully modifies FCI particles, using lithium silicate (Li 2 SiO 3 ), poly dimethyl siloxane (PDMS), and γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560), to synthesize Fe@SiO 2 @KH560@PDMS hybrid composite, related to its organic–inorganic hybrid coatings. The favorable hydrophobicity of organic–inorganic hybrid coatings with the static contact angle of 120° impeded the contact between corrosive medium and FCI core. The results of electrochemical experiments also confirmed its excellent corrosion resistance , since the corrosion potential E corr was positively shifted to 0.01 V, and the corrosion current I corr was three orders of magnitude lower than that of the unmodified FCI particles. Thermogravimetric (TG) analysis indicates that the presence of hybrid coatings also improved the thermal stability of the produced material towards oxidation . Furthermore, the results of molecular dynamics simulation reveal that the hybrid layer inhibits the diffusion of corrosive medium.
研究领域:
材料科学
·
电化学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2014
·
IF 4.058
Hong-Tao Fan,Qi Tang,Yang Sun,Zhi-Gang Zhang,Wen-Xiu Li
A Sb(III)-imprinted iodole-functionalized organic–inorganic hybrid sorbent was synthesized by combination of surface imprinting technique with sol–gel process for the selective removal of Sb(III) from aqueous media. The material was characterized by Fourier-transform infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis and nitrogen adsorption–desorption isotherms. Compared to the non-imprinted sorbent, the imprinted hybrid sorbent had higher selectivity and adsorption capacity for Sb(III) ion. The static adsorption capacity of the imprinted and non-imprinted sorbents for Sb(III) was 32.4 and 11.1 mg g −1 , respectively. The relative selectivity coefficients of the imprinted hybrid sorbent for Sb(III)/Cr(III) Sb(III)/Fe(III) and Sb(III)/As(III) were 13.2, 10.4 and 11.8, respectively. The imprinted hybrid sorbent possessed fast kinetics for the removal of Sb(III) from aqueous solution with a saturation time of 30 min, had a stable binding capacity in the range of pH 4–6, and could be used repeatedly. Both the pseudo-second-order kinetic model and the Langmuir model fit the experimental data well. It could be concluded from the thermodynamic parameters that the adsorption of Sb(III) on the imprinted hybrid sorbents was an exothermic and spontaneous process.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2022
·
IF 4.966
Beiping Dong,Ziang Li,Juncheng Liu,Lifang Nie
Coating antireflection film on the surface of glass cover is one of the important methods to improve the photoelectric conversion efficiency of solar cells. Sol-gel method is suitable for low cost and large area preparation of antireflection film. However, most of antireflective films prepared with sol-gel have not enough good mechanical properties , and their applications are restricted. A porous antireflection film was prepared with sol-gel, where the polyethylene glycol monomethyl ether (mPEG) was used as the porogen . The effects of the mPEG additive amount were investigated on the microstructure and properties of the film. The results showed that the transmittance of the film (the coated glass) first increases and then decreases with the increase of the amount of mPEG. When the amount of mPEG is 0.6 g, the average transmittance of the film in the wavelength range of 380–1100 nm is the highest, higher than that of glass substrate by 4.2 percentage points. The adhesion of the film reaches grade 0 and the hardness is greater than 9H. The efficiency of monocrystalline silicon solar cells could be increased from 11.65% to 12.04%, by a relative increase of 3.35%
研究领域:
材料科学
·
太阳能技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2021
·Vol. 99
·期 1
·169-177
·
IF 2.326
Cheng Ming,Liu Wensheng,Yao Shuwei,Wang Juan,Ma Yunzhu
Phase transformation is essentially important for the microstructures and properties of sol–gel prepared alumina fiber and powders. In this study, alumina precursor fiber and xerogels were prepared using the same aluminum carboxylate sol. The phase transformation and microstructure evolution of the precursor fibers and xerogels were investigated using TG-DSC, XRD, TEM, and SEM methods. The alumina precursor fiber and xerogels have similar chemical structures and Al(III) species. After preheated at 600 °C, most of the free water molecules, hydroxyl groups, nitrate acid radical, formic acid radicals, and acetic acid radicals are removed from the alumina precursor fiber and xerogels. The preheated fiber and xerogels exhibit amorphous phases. From the TG-DSC curves, the transformation temperature from γ-Al 2 O 3 to α-Al 2 O 3 in the preheated fiber is 30 °C lower than that in the preheated xerogels. The TEM results suggest that the fiber calcined at 1000 °C for 1 h can be completely transformed into α-Al 2 O 3 phase, while the xerogels need to be calcined at 1100 °C for 1 h to completely convert into the α-Al 2 O 3 phase. The difference in the phase transformation of the alumina fiber and xerogels was discussed in this paper.
研究领域:
材料科学
·
陶瓷学
✓ 已验证
产品关联
DOI
高影响因子
INTEGRATED FERROELECTRICS
·
2024
·
IF 0.7
Wenting Tu,Peisong Tang,Xinyu Mu,Wei Yong,Qiuxuan Li,Rong Chen
Using dysprosium oxide (Dy2O3), ammonium metavanadate (NH4VO3), nitric acid (HNO3) and citric acid (C6H8O7·H2O) as main raw materials, DyVO4 was successfully prepared by sol-gel method. DyVO4 samples were characterized by thermogravimetry differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), scanning electron microscope (SEM), diffuse reflectance spectrum (DRS) and Fourier transform infrared spectroscopy (FT-IR). Under condition of ultraviolet light, taking 10 mg/L methyl orange solution as simulated sewage, the effects of synthesis temperature and illumination time on the photocatalytic activity of DyVO4 were studied. The results show that pure tetragonal zircon DyVO4 samples can be obtained under calcination conditions of 600 °C to 900 °C. The average grain size is about 2 μm and the breadth of band gap is about 3.52 eV. The sample prepared at 800 °C has the best photocatalytic activity. Under ultraviolet light illumination for 150 min, the degradation rate of 10 mg/L methyl orange can reach nearly 100% in presence DyVO4. DyVO4 prepared by sol-gel method is a photocatalyst which has broad application prospect.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）