检索结果-南通市图书馆

World Journal of Engineering and Technology 2024年第1期12卷 170-184页

作者： Md. Barkat Ullah Yeasmin Akter Khodeja Afrin Md. Saiful Quddus Department of Applied Chemistry and Chemical Engineering Noakhali Science and Technology University Noakhali Bangladesh Bangladesh Council of Scientific and Industrial Research (BCSIR) Dhaka Bangladesh

This paper concentrates on the development of glasses with self-cleaning surfaces exhibiting high water contact angles. In this study, we prepared super-hydrophobic nano-ceramic coated glass based on titania & silica using simple sol-gel & dip coating methods and studied the best composition of the coatings by altering ratios of titanium tetraisopropoxide (TTIP)/tetraethyl orthosilicate (TEOS) with different homogenizing agents. We characterized the coatings by surface roughness measurement, percentage of optical transmission, static contact angle, near-infrared (NIR) transmission, and diffuse reflectance. The fabrication of coatings on glass substrates played an important role in increasing the water contact angle of about 95° and visible & NIR transmission of about 90%. We compared our modified glass substrate with commercial low emissivity (Low E) glass using X-ray diffraction (XRD) analysis, which showed pure amorphous surface claiming excellent wettability and thus the prepared glass substrate could have a variety of applications in different fields.

关键词： sol-gel Nano-Ceramic Coatings Self-Cleaning Glass Water Contact Angle Optical Transmission

Preparation and characterization of Rb-doped TiO_(2) powders for photocatalytic applications

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第2期43卷 555-561页

作者： Lu Jia Li-Mei Yang Wei Wang Song-Tao Huang Zheng Xu National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous MetalsBeijing100088China

TiO_(2)nanoparticles doped with different concentrations of Rb were prepared by sol–gel method.The crystal structures of samples were characterized by X-ray diffraction(XRD)and transmission electron microscopy(TEM).It was confirmed by the Rietveld refinement method that the as-prepared samples crystallize in anatase phase and Rb doping induces expansion and distortion of the crystal lattice.Compared with the pure TiO_(2),the Rb-doped nanoparticles have smaller crystal size and better dispersibility.Degradation rate of methylene blue was used to evaluate the photocatalytic activity of Rb–TiO_(2).It indicated that doping Rb into TiO_(2)can effectively improve the photocatalytic activity of TiO_(2)and the mechanisms were discussed in detail.When using the sample doped with 0.20%Rb,methylene blue degraded with the fastest rate(97%within 60 min).

关键词： Rb doping TiO_(2) Photocatalysis sol-gel

Facile sol-gel preparation of high-entropy multielemental electrocatalysts for efficient oxidation of methanol and urea

在线全文

学校读者我要写书评

暂无评论

Nano Research 2022年第6期15卷 5014-5023页

作者： Talifhani Mushiana Mustafa Khan Muhammad Imran Abdullah Ning Zhang Mingming Ma Department of Chemistry University of Science and Technology of ChinaHefei 230026China School of Biology Food and EnvironmentHefei UniversityHefei 230022China

High-entropy multi-elemental(HEM)electrocatalysts present superior catalytic performance due to the efficient synergism of their components.HEM electrocatalysts are usually prepared through hydrothermal reactions or calcination,which could generate undesired heterogeneous structures that hinder the exploration of the structure–property relationship of these HEM electrocatalysts.Herein,we report a sol-gel method to synthesize homogeneous HEM electrocatalysts for electro-oxidation of methanol and urea(methanol oxidation reaction(MOR)and urea oxidation reaction(UOR)),through an acid-catalyzed gelation at room temperature.With Ni as the primary component for MOR and UOR,Co can reduce the overpotentials,while Fe can increase the catalytic activities and durability.Borate and phosphate can tune the charge distribution in active sites and speed up the reaction kinetics through fast proton transfer.Thus,the optimal Ni_(2)Fe_(0.5)Co_(0.5)-BP HEM catalyst demonstrates superior catalytic activity together with good durability and great resistance to CO poisoning.In addition,a direct methanol fuel cell with Ni_(2)Fe_(0.5)Co_(0.5)-BP electrode can not only provide power,but also produce formic acid with high yield and high Faraday efficiency.This work presents a simple strategy to prepare high-performance HEM electrocatalysts for fuel cells and production of valueadded chemicals.

关键词： catalytic oxidation reaction high-entropy multi-elemental electrocatalysts sol-gel formic acid

Application of g-C_(3)N_(4)/sol-gel nanocomposite on AM60B magnesium alloy and investigation of its properties

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2023年第6期30卷 1113-1127页

作者： Roghaye Samadianfard Davod Seifzadeh Burak Dikici Corrosion and Industrial Electrochemistry Research Laboratory University of Mohaghegh ArdabiliArdabil P.O.Box 179Iran Ataturk University Department of Metallurgical and Materials EngineeringErzurum 25240Turkey

To protect the AM60B magnesium alloy from corrosion,a sol-gel coating containing hydroxylated g-C_(3)N_(4)nanoplates was applied.The chemical composition of the hydroxylated g-C_(3)N_(4)nanoplates was investigated using X-ray photoelectron spectroscopy(XPS).The hydroxylation process did not affect the crystal size,specific surface area,pore volume,average pore diameter,and thermal stability of the g-C_(3)N_(4)nanoplates.After incorporating pristine and hydroxylated g-C_(3)N_(4)nanoplates,dense sol-gel coatings were obtained.Transmission electron microscopy(TEM)revealed the uniform distribution of the modified g-C_(3)N_(4)in the coating.The average roughness of the coating was also reduced after adding the modified nanoplates due to the decreased aggregation tendency.Electrochemical impedance spectroscopy(EIS)examinations in simulated acid rain revealed a significant improvement in the anticorrosion properties of the sol-gel film after the addition of the modified g-C_(3)N_(4)due to the chemical bonding of the coating to the nanoplates.

关键词： Mg alloy corrosion protection sol-gel g-C_(3)N_(4)nanocomposite electrochemical impedance spectroscopy

Combining the 8-hydroxyquinoline intercalated layered double hydroxide film and sol-gel coating for active corrosion protection of the magnesium alloy

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2022年第3期29卷 536-546页

作者： Yahya Jafari Tarzanagh Davod Seifzadeh Roghaye Samadianfard Applied Chemistry Department University of Mohaghegh ArdabiliArdabil ***Iran

8-hydroxyquinoline(8-HQ)intercalated layered double hydroxides(LDH)film as underlayer and sol-gel layer was combined for active corrosion protection of the AM60B magnesium alloy.The LDH,LDH/sol-gel,and LDH@HQ/sol-gel coatings were analyzed using the scanning electron microscopy(SEM),field emission scanning electron microscopy(FESEM),energy dispersive X-ray spectroscopy(EDS),X-ray diffraction(XRD),atomic force microscopy(AFM),and electrochemical impedance spectroscopy(EIS)methods.The SEM images showed that the surface was entirely coated by the LDH film composed of vertically-grown nanosheets.The same morphology was observed for the LDH/sol-gel and LDH@HQ/sol-gel coatings.Also,almost the same topography was observed for both composite coatings except that the LDH@HQ/sol-gel coating had relatively higher surface roughness.Although the LDH film had the same impedance behavior as the alloy sample in 3.5wt%NaCl solution,its corrosion resistance was much higher,which could be due to its barrier properties as well as to the trap-ping of the chloride ions.Similar to the LDH film,the corrosion resistance of the LDH/sol-gel composite diminished with increasing the ex-posure time.However,its values were much higher than that of the LDH film,which was mainly related to the sealing of the solution path-ways.The LDH@HQ/sol-gel composite showed much better anti-corrosion properties than the LDH/sol-gel coating due to the adsorption of the 8-HQ on the damaged areas through the complexation.

关键词： magnesium alloy sol-gel layered double hydroxides corrosion coating

Photoelectrochemical activity of ZnO:Ag/rGO photo-anodes synthesized by two-steps sol-gel method

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2022年第5期31卷 691-702页

作者： D Ben Jemia M Karyaoui M A Wederni A Bardaoui M V Martinez-Huerta M Amlouk R Chtourou Laboratory of Nanomaterials and Renewable Energy Systems LANSER Research and Technology Center of EnergyBorj-Cedria Science and Technology ParkBP 952050 Hammam-LifTunisia Faculty of Science of Tunis University of Tunis El ManarTunisia Laboratory of Physics of Materials and Nanomaterials Applied to the Environment(LaPhyMNE) Faculty of Sciences of GabesCite ErriadhUniversity of Gabes6079 GabesTunisia lnstitute of Catalysis and Petrochemistry CSICin MadridSpain Laboratory of Nanomaterials Nanotechnology and Energy(L2NE)University of Tunis El ManarTunisia

This work investigated the influence of silver plasmon and reduced graphene oxide(r GO)on the photoelectrochemical performance(PEC)of Zn O thin films synthesized by the sol-gel method.The physicochemical properties of the obtained photo-anodes were systematically studied by using several characterization techniques.The x-ray diffraction analysis showed that all samples presented hexagonal wurtzite structure with a polycrystalline nature.Raman and energy dispersive x-ray(EDX)studies confirmed the existence of both Ag and r GO in Zn O:Ag/r GO thin films.The estimated grain size obtained from scanning electron microscopy(SEM)analysis decreased with Ag doping,then increased to a maximum value after r GO addition.The UV-vis transmission spectra of the as-prepared Zn O:Ag and Zn O:Ag/r GO thin films have shown a reduction in the visible range with a redshift at the absorption edges.The bandgaps were estimated to be around 3.17 e V,2.7 e V,and 2.52 e V for Zn O,Zn O:Ag,and Zn O:Ag/r GO,respectively.Moreover,the electrical measurements revealed that the charge exchange processes were enhanced at the Zn O:Ag/r GO/electrolyte interface,accompanied by an increase in the(PEC)performance compared to Zn O and Zn O:Ag photo-anodes.Consequently,the photocurrent density of Zn O:Ag/r GO(0.2 m A·cm^(-2)) was around 4 and 2.22 times higher than photo-anodes based on undoped Zn O(0.05 m A·cm^(-2)) and Zn O:Ag(0.09 m A·cm^(-2)),respectively.Finally,from the flat band potential and donor density,deduced from the Mott-Schottky,it was clear that all the samples were n-type semiconductors with the highest carrier density for the Zn O:Ag/r GO photo-anode.

关键词： zinc oxide reduced graphene oxide silver doping sol-gel photoelectrochemical performance

Highly impermeable and flexible silica encapsulation films synthesized by sol-gel process

在线全文

学校读者我要写书评

暂无评论

Nano Research 2022年第8期15卷 7476-7483页

作者： Si-Hoon Kim Gyeong-Seok Hwang Donghwan Koo Dong-Hyun Seo Ye-Pil Kwon Hansuek Lee Hyesung Park Eun-chae Jeon Ju-Young Kim School of Materials Science and Engineering University of UlsanTechno saneop-ro 55beon-gil 12Ulsan 44776Republic of Korea Department of Materials Science and Engineering Ulsan National Institute of Science and Technology(UNIST)UNIST-gil 50Ulsan 44919Republic of Korea Department of Physics Korea Advanced Institute of Science and Technology(KAIST)Daehak-ro 291Deajeon 34141Republic of Korea Graduate School of Semiconductor Materials and Devices Ulsan National Institute of Science and Technology(UNIST)UNIST-gil 50Ulsan 44919Republic of Korea

Silica thin films synthesized sol–gel process are proposed as flexible encapsulation materials.A sol–gel process provides a dense and stable amorphous silica structure,yielding an extremely high elastic deformation limit of 4.9%and extremely low water vapor transmission rate(WVTR)of 2.90×10^(−4)g/(m^(2)∙day)at 60℃and relative humidity of 85%.The WVTR is not degraded by cyclic bending deformations for the bending radius corresponding to a tensile strain of 3.3%in the silica encapsulation film,implying that the silica thin film is robust against the formation of pinhole-type defects by cyclic bending deformations.Flexible organic solar cells encapsulated with the silica films operate without degradation in power conversion efficiency for 50,000 bending cycles for a bending radius of 6 mm.

关键词： silica thin film sol-gel flexible encapsulation mechanical reliability flexible organic solar cell

Nd3+-doped silica glass and fiber prepared by modified sol-gel method

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Optics Letters 2022年第9期20卷 38-42页

作者：陈应刚林治全王亚飞王孟张磊焦艳董贺贺王世凯于春雷胡丽丽 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100039China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

Large-size Al^(3+)/Nd^(3+)co-doped silica glass with 5000 ppm Nd^(3+)and 50,000 ppm Al^(3+)doping concentrations was prepared by the modified sol-gel method combined with high-temperature melting and molding technology.Electron probe microanalyzer tests indicated that high doping homogeneity was achieved with this sample preparation method.The spectral properties of the Nd^(3+)ions were evaluated.Nd^(3+)-doped silica fiber(NDF)with a core-to-clad ratio of 20/125μm was drawn from the preform with the Al^(3+)/Nd^(3+)co-doped silica glass as the core.In the laser oscillation experiment,a maximum output power of 14.6 W at 1.06μm with a slope efficiency of 39.6%was obtained from the NDF pumped by a commercial808 nm laser diode.To the best of our knowledge,this is the highest laser power reported for an NDF operated at 1060 nm and prepared by a non-chemical vapor deposition method.In the master oscillator power amplifier experiment,a maximum power of 16.6 W corresponding to a slope efficiency of 30.5%at 1061 nm was also demonstrated.The laser performance of the NDF exhibited the great advantages and potential of the modified sol-gel method in fabricating Nd^(3+)-doped silica glass for a new type of NDFs like large mode area fibers and fibers with large diameter ratio of core/cladding.

关键词： Nd3+-doped silica sol-gel doping homogeneity.

Post-treatment of 351 nm SiO_(2) antireflective coatings for high power laser systems prepared by the sol-gel method

在线全文

学校读者我要写书评

暂无评论

Chinese Optics Letters 2022年第1期20卷 89-93页

作者：沈斌熊怀张旭陈知亚庞向阳郭亚晶梁成杰李海元 Key Laboratory of High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Different post-treatment processes involving the use of ammonia and hexamethyldisilazane(HMDS) were explored for application to 351 nm third harmonic generation SiO_(2)antireflective(3ω SiO_(2)AR) coatings for high power laser systems prepared by the sol-gel method.According to experimental analysis,the 3ω SiO_(2)AR coatings that were successively post-treated with ammonia and HMDS at 150℃ for 48 h and again heat-treated at 180℃ for 2 h(N/H 150+180 AR) were relatively better.There were relatively fewer changes in the optical properties of the N/H 150+180 AR coating under a humid and polluted environment,and the increase in defect density was slow in high humidity environments.The laser-induced damage threshold of the N/H 150+180 AR coating reached 15.83 J/cm;(355 nm,6.8 ns),a value that meets the basic requirements of high power laser systems.

关键词： optical materials antireflection coatings sol-gel optics at surfaces laser damage thin films optical properties

Preparations of TiO_2 film coated on foam nickel substrate by sol-gel processes and its photocatalytic activity for degradation of acetaldehyde

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2007年第1期19卷 80-85页

作者： HU Hai XIAO Wen-jun YUAN Jian SHI Jian-wei CHEN Ming-xia SHANG GUAN Wen-feng Research Center for Combustion and Environment Technology Shanghai Jiao Tong University. Shanghai 200030 China

Anatase TiO2 films were successfully prepared on foam nickel substrates by sol-gel technique using tetrabutyl titanate as precursor. The characteristics of the TiO2 films were investigated by XPS, XRD, FE-SEM, TEM and UV-Vis absorption spectra. The photocatalytic activities of TiO2 films were investigated by photocatalytic degradation reactions of gaseous acetaldehyde, an indoor pollutant, under ultraviolet light irradiation. It was found that Ni^2＋ doping into TiO2 films due to the foam nickel substrates resulted in the extension of absorption edges of TiO2 films from UV region to visible light region. The pre-heating for foam nickel substrates resulted in the formation of NiO layer, which prevented effectively the injection of photogenerated electrons from TiO2 films to metal nickel. The TiO2 films displayed high photocatalytic activity for the degradation of acetaldehyde, and were enhanced by calcining the substrates and coating TiO2 films repeatedly. The high activity was mainly attributed to the improvement of the characteristics of substrate surface and the increase of active sites on photocatalyst.

关键词： photocatalyst TiO2 films foam nickel sol-gel acetaldehyde degradation