sol-gel

摘要： In this study, the synthesis of LiCo1-XSmXOy powders (X = 0.002, 0.004, 0.006, 0.008, and 0.1) by the sol-gel method and the influence of Sm on their structural and morphological properties is reported for the first time. The results of x-ray diffraction (XRD) studies show that LiCoO2 powders synthesized at temperatures up to 700°C present a characteristic hexagonal crystalline phase of the α-NaFeO2 type (space group R-3m), revealing a shift in the (0 0 3) Bragg reflection, which reflects the presence of Sm in the crystalline structure. The morphology was spheroidal and, on average, 122 nm in size. Based on the data obtained, LiCo1-XSmXOy powders (X = 0.002, 0.004, 0.006, 0.008, and 0.1) show promise as a material for use in the cathodes of lithium-ion batteries.

摘要： 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.

摘要： Here we demonstrate a theory-driven, novel dual-shell coating system of Li_(2)SrSiO_(4) and Al_(2)O_(3), achieved via a facile and scalable sol-gel technique on LiCoO_(2) electrode particles. The optimal thickness of each coating can lead to increased specific capacity(~185 m Ah/g at 0.5 C-rate) at a cut-off potential of 4.5 V, and greater cycling stability at very high C rates(up to 10 C) in half-cells with lithium metal. The mechanism of this superior performance was investigated using a combination of X-ray and electron characterization methods. It shows that the results of this investigation can inform future studies to identify still better dual-shell coating schemes, achieved by such industrially feasible techniques, for application on similar, nickel-rich cathode materials.

摘要： Erbium-doped barium titanate(BaTiO_(3):Er)xerogel film with a thickness of about 500 nm was formed on the porous strontium titanate(SrTiO_(3))xerogel film on Si substrate after annealing at 800°C or 900°C.The elaborated structures show room tempera-ture upconversion luminescence under 980 nm excitation with the photoluminescence(PL)bands at 523,546,658,800 and 830 nm corresponding to^(2)H1_(1/2)→^(4)I_(15/2),^(4)S_(3/2)→^(4)I_(15/2),^(4)F_(9/2)→^(4)I_(15/2)and^(4)I_(9/2)→^(4)I_(15/2)transitions of trivalent erbium.Raman and X-ray diffraction(XRD)analysis of BaTiO_(3):Erporous SrTiO_(3)Si structure showed the presence of perovskite phases.Its excellent up-conversion optical performance will greatly broaden its applications in perovskite solar cells and high-end anti-counterfeiting technologies.

摘要： Through the impregnation method, Ag catalysts with different support (such as TiO2 and γ-Al2O3) were prepared and then tested for catalytic oxidation of formaldehyde (HCHO) at low temperatures. The Ag/TiO2 catalyst exhibited strong catalytic performance, converting HCHO to CO2 and H2O at around 95°C. However, the Ag/Al2O3 catalysts showed much lower activity and reached 100% conversion at 125°C. The Ag-based catalysts were next characterized by several methods (XRD, TEM, FT-R, BET and H2-TPR). Results of characterization revealed that support dramatically impacts the size and dispersion of Ag particles. The XRD analysis showed the existence of different peaks of the silver on the surface of Al2O3 in the contrast with TiO2 no specific peaks exist. Therefore, the size of the Ag particles and their dispersion are the most important factors that affect their catalytic performance for formaldehyde oxidation. In terms of catalytic performance for HCHO oxidation, the Ag/TiO2 catalyst possesses the best Ag dispersion, as well as the smallest Ag particle size.

摘要： Barium titanate tin oxides BaTi0.9Sn0.1O3 referred to as (BTSO) doped with 0.5Er3+ and co-doped with (0.75 and 1) Yb3+ ions, were prepared using a modified sol-gel method and calcinated at 1050?C in the air for 4 h. The influence of the selected rare earth element on the structure morphology, dielectric properties behavior was investigated. From TEM micrographs, it has appeared that the particles have a spherical shape with a small size in nanoscale. The average particle size is determined both by TEM and XRD diffraction was found to be in agreement and within the range between 45.9 and 57.7 nm. The effects of Lanthanide incorporation on the evolution of these nano-crystalline structures were followed by XRD and (FTIR). The XRD patterns give rise to a single perovskite phase, while the tetragonality was found to decrease gradually with Er3+ and Er3+/Yb3+ ions, respectively. FTIR results showed enhancement of the crystallinity and the absence of carbonates upon increasing Yb3+ ions concentration from 0.75 up to 1 mol%. The dielectric and conductivity properties were found to be enhanced by the nature and the concentration of the lanthanide element (Er3+, Yb3+) in the BTSO host lattice. The Curie temperature (Tc) shifted to a lower value from 117 for BTSO: 0.5Er to 93 for BTSO: 0.5Er/1Yb and the permittivity ε’ increased from 3972 to 6071, so BTSO: 0.5Er/1Yb good crystalline material candidate for capacitors application due to its higher permittivity.

摘要： 目的研究一种将Stober法制备的SiO_(2)纳米微球分散在含硅溶胶体系中,在聚酰亚胺(PI,Kapton)表面制备含SiO_(2)微纳米颗粒涂层的新方法,并利用该涂层提高Kapton薄膜的使用寿命和抗原子氧(atomic oxygen,AO)侵蚀能力。方法用正硅酸乙酯(TEOS)在碱性条件下制备Stober微球,用3-氨丙基三乙氧基硅烷(APTES)在酸性条件下制备含硅溶胶。将Stober微球均匀分散到溶胶中,用提拉镀膜方法在经低浓度NaOH水热处理后的Kapton薄膜表面,制备含SiO_(2)微纳米颗粒的涂层。在束流密度为1.43×10~(16) atoms/(cm^(2)·s),辐照时间为6 h的AO环境中进行模拟试验。用SEM扫描电镜和AFM原子力显微镜表征试验前后样品的表面形貌。结果 AO辐照后,原始Kapton薄膜的质量损失和AO侵蚀率分别为1.39 mg/cm^(2)和3.17×10^(-24) cm^(3)/atom,且Kapton表面被严重侵蚀;而有涂层的Kapton样品,质量损失和AO侵蚀率分别下降为0.10 mg/cm^(2)和0.22×10^(-24) cm^(3)/atom,侵蚀率只相当于原始Kapton的6.9%。结论采用Stober与sol-gel相结合的方法,提高了所制备涂层中SiO_(2)的含量。模拟试验表明,该涂层提高了样品的抗AO侵蚀能力。此制备方法简单实用,对于长寿命航天器中聚合物材料的AO防护,具有一定的研究意义。

摘要： In this study,AleCuO nanocomposites were fabricated by sol-gel method.As a contrast,the thermite was prepared by physical mixing at the equivalence ratio of 0.5,1,2,respectively.The intermediates and samples as prepared were characterized by SEM and XRD.The exothermic properties of the two samples prepared at different equivalence ratios were tested and the reaction products were characterized by XRD.The SEM results show that the sample prepared by the sol-gel method demonstrates a micron-sized agglomerated sphere formed by a mutual wrapping of Al NPs and CuO NPs,and the particles are evenly distributed in the agglomerate.In addition,when the content of Al powder is seriously insufficient,the heat release of the sample prepared by physical mixing is 1.6 times that of by sol-gel method.With the increase of Al powder content,the exothermic properties of Al/CuO NPs prepared by sol-gel method began to increase significantly compared with physical mixing and the difference is 1.5 times when the equivalence ratio increases to 2.It can be concluded that the reason for this result may be attributed to the different mass transfer modes of components due to the different morphologies of samples.

摘要： The present study aims to develop multilayer barrier-bioactive hybrid sol-gel coatings from a mixture of the silane precursors tetraethylorthosilicate(TEOS)and glycidoxypropyltriethoxysilane(GPTMS)deposited on the Elektron 21 magnesium alloy.The purpose of the inner layer(barrier coating)was to provide corrosion protection to the magnesium alloy,whereas the outer layer(bioactive coating)was doped with different Ca and Mg contents to produce a bioactive material.The coatings were characterised using scanning electron microscopy(SEM)and their corrosion behaviour was evaluated by anodic polarisation and electrochemical impedance spectroscopy after immersion in simulated body fluid(SBF)at 37±0.5°C.The experimental results showed that the multilayer coatings increased the corrosion resistance of the alloy up to three orders of magnitude during immersion in SBF solution.On the other hand,the presence of Ca and Mg in the bioactive coating promoted the growth of apatite-like phases.However,an increment of salt content favoured the formation of porous coatings,which allowed the access of the electrolyte to the substrate leading to their rapid deterioration.Despite the latter,this research endorses the premise that the TEOS-GPTMS hybrid system represents a promising alternative to produce bifunctional barrier-bioactive coatings.

摘要： Massive oily wastewater discharged from industrial production and human daily life have been an urgent environmental and ecological challenge.Superhydrophobic materials have attracted tremendous attention due to their unique properties and potential applications in the treatment of wastewater.In this study,a novel superhydrophobic/superoleophilic composite melamine sponge modified with dual silanized SiO_(2) microspheres was fabricated simply by a two-step sol-gel method using vinyltriethoxysilane and hexadecyltrimethoxysilane as functional agent,which exhibited a water contact angle of 153.2°and a water sliding contact angle of 4.8°.Furthermore,the composite sponge showed the excellent oil adsorption performance and the compressive elasticity reaching up to 130 g·g^(-1) of dichloromethane and 33.1 kPa of compressive stress.It was worth noting that the composite sponge presented the excellent separation efficiency(up to 99.5%)in the processes of continuous oil/water separation.The robust superhydrophobic composite melamine sponge provided the possibility with the practical application for oil-water separation.

摘要： 论文介绍了利用溶胶凝胶(sol-gel)键合技术制作的Si基集成共振腔增强型(RCE)光电探测器。键合界面在RCE结构的下DBR和Si衬底之间，键合温度为300°C。器件峰值响应波长在1552.7nm，峰值半高宽(FHWM)为6.4nm，响应度为0.6A/W，带宽为17.05GHz。

摘要： 论文介绍了利用溶胶凝胶(sol-gel)键合技术制作的Si基集成共振腔增强型(RCE)光电探测器。键合界面在RCE结构的下DBR和Si衬底之间，键合温度为300°C。器件峰值响应波长在1552.7nm，峰值半高宽(FHWM)为6.4nm，响应度为0.6A/W，带宽为17.05GHz。

摘要： 论文介绍了利用溶胶凝胶(sol-gel)键合技术制作的Si基集成共振腔增强型(RCE)光电探测器。键合界面在RCE结构的下DBR和Si衬底之间，键合温度为300°C。器件峰值响应波长在1552.7nm，峰值半高宽(FHWM)为6.4nm，响应度为0.6A/W，带宽为17.05GHz。

摘要： 论文介绍了利用溶胶凝胶(sol-gel)键合技术制作的Si基集成共振腔增强型(RCE)光电探测器。键合界面在RCE结构的下DBR和Si衬底之间，键合温度为300°C。器件峰值响应波长在1552.7nm，峰值半高宽(FHWM)为6.4nm，响应度为0.6A/W，带宽为17.05GHz。

摘要： 本文采用sol-gel复合料浆热压滤法制备YPSZ热障涂层和Al2O3-ZrO2-Y2O3抗氧化涂层。研究表明，使用sol-gel复合料浆热压滤法可以一次性获得表面完整，没有裂纹，厚度可达数百微米，与基体结合紧密的复合陶瓷涂层。涂层的完整致密程度随粉胶比及施加压力的增加而增高。FE-SEM观测显示，YPSZ热障涂层具有纳米/微米/微孔复合结构，隔热测试结果表明，YPSZ热障涂层具有优异的隔热性能，且其隔热性能随胶粉比的增加而增高。A12O3-ZrO2-Y2O3复合涂层具有YPSZ/Al2O3颗粒镶嵌于Al2O3-Y2O3空间网络膜的复合结构。高温氧化实验表明，Al2O3-Y2O3空间网络膜能够有效阻碍氧离子扩散，镶嵌的YPSZ颗粒可以调节复合涂层的热膨胀系数，因此涂层表现出优异的抗高温氧化与剥落性能。

摘要： 本文采用sol-gel复合料浆热压滤法制备YPSZ热障涂层和Al2O3-ZrO2-Y2O3抗氧化涂层。研究表明，使用sol-gel复合料浆热压滤法可以一次性获得表面完整，没有裂纹，厚度可达数百微米，与基体结合紧密的复合陶瓷涂层。涂层的完整致密程度随粉胶比及施加压力的增加而增高。FE-SEM观测显示，YPSZ热障涂层具有纳米/微米/微孔复合结构，隔热测试结果表明，YPSZ热障涂层具有优异的隔热性能，且其隔热性能随胶粉比的增加而增高。A12O3-ZrO2-Y2O3复合涂层具有YPSZ/Al2O3颗粒镶嵌于Al2O3-Y2O3空间网络膜的复合结构。高温氧化实验表明，Al2O3-Y2O3空间网络膜能够有效阻碍氧离子扩散，镶嵌的YPSZ颗粒可以调节复合涂层的热膨胀系数，因此涂层表现出优异的抗高温氧化与剥落性能。

摘要： 本文采用sol-gel复合料浆热压滤法制备YPSZ热障涂层和Al2O3-ZrO2-Y2O3抗氧化涂层。研究表明，使用sol-gel复合料浆热压滤法可以一次性获得表面完整，没有裂纹，厚度可达数百微米，与基体结合紧密的复合陶瓷涂层。涂层的完整致密程度随粉胶比及施加压力的增加而增高。FE-SEM观测显示，YPSZ热障涂层具有纳米/微米/微孔复合结构，隔热测试结果表明，YPSZ热障涂层具有优异的隔热性能，且其隔热性能随胶粉比的增加而增高。A12O3-ZrO2-Y2O3复合涂层具有YPSZ/Al2O3颗粒镶嵌于Al2O3-Y2O3空间网络膜的复合结构。高温氧化实验表明，Al2O3-Y2O3空间网络膜能够有效阻碍氧离子扩散，镶嵌的YPSZ颗粒可以调节复合涂层的热膨胀系数，因此涂层表现出优异的抗高温氧化与剥落性能。

摘要： 本文采用sol-gel复合料浆热压滤法制备YPSZ热障涂层和Al2O3-ZrO2-Y2O3抗氧化涂层。研究表明，使用sol-gel复合料浆热压滤法可以一次性获得表面完整，没有裂纹，厚度可达数百微米，与基体结合紧密的复合陶瓷涂层。涂层的完整致密程度随粉胶比及施加压力的增加而增高。FE-SEM观测显示，YPSZ热障涂层具有纳米/微米/微孔复合结构，隔热测试结果表明，YPSZ热障涂层具有优异的隔热性能，且其隔热性能随胶粉比的增加而增高。A12O3-ZrO2-Y2O3复合涂层具有YPSZ/Al2O3颗粒镶嵌于Al2O3-Y2O3空间网络膜的复合结构。高温氧化实验表明，Al2O3-Y2O3空间网络膜能够有效阻碍氧离子扩散，镶嵌的YPSZ颗粒可以调节复合涂层的热膨胀系数，因此涂层表现出优异的抗高温氧化与剥落性能。

摘要： 本文采用溶胶凝胶(Sol-Gel)和两步氢还原法,成功制备了掺杂复合RE2O3(RE2O3=La2O3+Y2O3)的稀土钼粉末.采用放电等离子快速烧结方法(SPS)制备了致密样品.对其次级电子发射性能进行研究.研究结果表明:活化工艺极大提高样品次级发射性能,最佳激活温度降低100-200°C,最大次级发射系数提高近1倍,活化工艺降低样品中氧含量,消除样品在高温激活时发生的金属氧化现象.随着样品中Y2O3含量逐步提高,样品组织细化明显,进而改善了阴极材料的次级发射性能.

摘要： 本文采用溶胶凝胶(Sol-Gel)和两步氢还原法,成功制备了掺杂复合RE2O3(RE2O3=La2O3+Y2O3)的稀土钼粉末.采用放电等离子快速烧结方法(SPS)制备了致密样品.对其次级电子发射性能进行研究.研究结果表明:活化工艺极大提高样品次级发射性能,最佳激活温度降低100-200°C,最大次级发射系数提高近1倍,活化工艺降低样品中氧含量,消除样品在高温激活时发生的金属氧化现象.随着样品中Y2O3含量逐步提高,样品组织细化明显,进而改善了阴极材料的次级发射性能.