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Preparation and Properties of Ti_(3)SiC_(2)-modified High Silica/Phenolic Aerogel Composite
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作者 CAO Wenjing LIU Yiming +4 位作者 ZHAO Dongmei WAN Xiaobo LIU Yang HUANG Kun SHI Minxian 《Journal of Wuhan University of Technology(Materials Science)》 2025年第6期1563-1571,共9页
A Ti_(3)SiC_(2)-modified high-silica oxygen/phenolic aerogel composite with excellent oxidation resistance and high-temperature performance was prepared.The experimental results show that the obtained composite has si... A Ti_(3)SiC_(2)-modified high-silica oxygen/phenolic aerogel composite with excellent oxidation resistance and high-temperature performance was prepared.The experimental results show that the obtained composite has significantly improved oxidation resistance.When the addition amount of Ti_(3)SiC_(2)is 75%,the carbonization volume shrinkage rate of the composite after aerobic static combustion is only 5.95%.At the same time,the LAR and MAR after 30 seconds of oxyacetylene ablation under a heat flux density of 1.5 MW/m2 are 0.0307 mm/s and 0.0149 g/s,respectively.The compressive strength after aerobic static combustion at 1000℃is up to 20.43%of that before aerobic static combustion,which is 1.99 times that of the unfilled material,significantly improving the high-temperature mechanical properties of the composite. 展开更多
关键词 Ti_(3)SiC_(2) phenolic aerogel composites high silica fiber thermal conductivity
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Effect of Al_(2)O_(3)fiber on twin intersections-induced dynamic recrystallization in fine-grained TiAl matrix composite 被引量:3
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作者 Yaofeng Luo Yan Wang +2 位作者 Li Wang Bin Liu Yong Liu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第5期1-14,共14页
Dynamic recrystallization(DRX)is of great significance for the thermomechanical processing and microstructural regulation of TiAl intermetallics.However,the underlying DRX mechanism remains poorly understood.In this s... Dynamic recrystallization(DRX)is of great significance for the thermomechanical processing and microstructural regulation of TiAl intermetallics.However,the underlying DRX mechanism remains poorly understood.In this study,an Avrami kinetics model for DRX was established,which was capable of predicting the DRX fraction accurately.In addition,the effect of Al_(2)O_(3)short fiber on the DRX mechanisms of TiAl matrix composite during the isothermal compression was investigated for the first time.The re-sults showed that other than inhibiting DRX by particles in the TiAl matrix composites,the addition of Al_(2)O_(3)short fiber accelerated a novel DRX process,which was induced by twinning and twin intersec-tions(TDRX).Thus,this composite exhibited a higher DRX rate than that of the as-cast TiAl monolithic alloy.The origin of the twin intersection and TDRX for the composite was revealed.The stress concentration near the Al_(2)O_(3)fiber was above the critical shear stress for twinning and thus was favorable for the formation of twinning and twin intersections.The high stored strain energy at the regions of twins and twin intersections provided the driving force for TDRX.TDRX accelerated the grain refinement in the TiAl matrix near the Al_(2)O_(3)fiber.The present findings would provide a new perspective on DRX mechanisms,and provide the scientific guidance for optimizing the microstructures of TiAl matrix composites. 展开更多
关键词 TiAl matrix composite Al_(2)O_(3)fiber Twin intersection Dynamic recrystallization
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Preparation of Z-scheme WO_3(H_2O)_(0.333)/Ag_3PO_4 composites with enhanced photocatalytic activity and durability 被引量:9
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作者 Zhen Li Xia Wang +3 位作者 Jinfeng Zhang Changhao Liang Luhua Lu Kai Dai 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第3期326-334,共9页
Ag3PO4 is widely used in the field of photocatalysis because of its unique activity. However, photocorrosion limits its practical application. Therefore, it is very urgent to find a solution to improve the light corro... Ag3PO4 is widely used in the field of photocatalysis because of its unique activity. However, photocorrosion limits its practical application. Therefore, it is very urgent to find a solution to improve the light corrosion resistance of Ag3PO4. Herein, the Z-scheme WO3(H2O)0.333/Ag3PO4 composites are successfully prepared through microwave hydrothermal and simple stirring. The WO3(H2O)0.333/Ag3PO4 composites are characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and UV-Vis spectroscopy. In the degradation of organic pollutants, WO3(H2O)0.333/Ag3PO4 composites exhibit excellent performance under visible light. This is mainly attributed to the synergy of WO3(H2O)0.333 and Ag3PO4. Especially, the photocatalytic activity of 15%WO3(H2O)0.333/Ag3PO4 is the highest, and the methylene blue can be completely degraded in 4 min. In addition, the stability of the composites is also greatly enhanced. After five cycles of testing, the photocatalytic activity of 15%WO3(H2O)0.333/Ag3PO4 is not obviously decreased. However, the degradation efficiency of Ag3PO4 was only 20.2%. This indicates that adding WO3(H2O)0.333 can significantly improve the photoetching resistance of Ag3PO4. Finally, Z-scheme photocatalytic mechanism is investigated. 展开更多
关键词 Photocatalysis Ag3PO4 wo3(H2O)0.333 compositeS Z-scheme
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Preparation and Characterization of Alumina-coated Hollow Quartz Fiber Reinforced Al_(2)O_(3)-SiO_(2) Aerogel Composite 被引量:2
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作者 ZHANG Han LIU Junlong ZHU Shizhen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第3期324-330,共7页
Al_(2)O_(3)–SiO_(2)sols were synthesized by using aluminum chloride hex hydrate and tetraethoxysilane(TEOS)as precursors,deionized water and ethanol mixture as the solvent,and propylene oxide as the coagulant aids.Al... Al_(2)O_(3)–SiO_(2)sols were synthesized by using aluminum chloride hex hydrate and tetraethoxysilane(TEOS)as precursors,deionized water and ethanol mixture as the solvent,and propylene oxide as the coagulant aids.Alumina coatings were prepared on the surfaces of hollow quartz filament fiber,then a new lightweight and thermal insulating material were successfully prepared by impregnatingAl_(2)O_(3)–SiO_(2)sol into a needle fabric made by coated hollow quartz filament fiber.The coated quartz fiber,aerogels and composites were characterized by Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),energy dispersive spectroscopy(EDS),nitrogen adsorption-desorption(BET),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and tensile tests.The effects of different fiber and calcination temperatures on the microstructures and properties ofAl_(2)O_(3)–SiO_(2)composite aerogels were investigated.The test results indicate that the mechanical properties of the aerogels are improved by introducing quartz filament fabrics and the introduction of alumina coating improves the thermal stability of the material.Compared to other fibers,Al_(2)O_(3)-coated hollow quartz fiber has significant advantages as reinforcement for composite,and their tensile strength is well retained after high temperature heat treatment. 展开更多
关键词 Al_(2)O_(3)-SiO_(2)aerogel composites hollow quartz fiber thermal insulation property thermal stability
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Bi/TiO_(2)∶Sm^(3+)复合纤维的制备及可见光催化降解抗生素洛美沙星
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作者 李跃军 曹铁平 孙大伟 《硅酸盐通报》 北大核心 2025年第5期1918-1926,共9页
以静电纺丝技术制备TiO_(2)∶Sm^(3+)纳米纤维,结合原位水热法,在葡萄糖酸钠作用下,合成Bi/TiO_(2)∶Sm^(3+)复合纤维。利用XRD和XPS表征样品的物相和组成,利用SEM和TEM观察样品的微观形貌,利用紫外-可见漫反射光谱和瞬态光电流等分析... 以静电纺丝技术制备TiO_(2)∶Sm^(3+)纳米纤维,结合原位水热法,在葡萄糖酸钠作用下,合成Bi/TiO_(2)∶Sm^(3+)复合纤维。利用XRD和XPS表征样品的物相和组成,利用SEM和TEM观察样品的微观形貌,利用紫外-可见漫反射光谱和瞬态光电流等分析样品的光电性能。结果表明,Sm^(3)+进入TiO_(2)晶格,占据Ti^(4+)的位置,造成TiO_(2)晶格膨胀,引起晶格畸变。稀土掺杂引入的晶格缺陷能够提高TiO_(2)的费米能级,增加表面能量壁垒,使光生电子和空穴在表面的复合概率降低;金属Bi通过表面等离子体共振效应,结合稀土元素丰富的能级结构和4f电子跃迁特性,对TiO_(2)进行双重修饰改性,进一步提高了TiO_(2)的光催化活性和稳定性。可见光照5 h,Bi/TiO_(2)∶Sm^(3+)复合纤维对洛美沙星的降解效果最佳,达到97.37%,分别是Sm^(3+)∶TiO_(2)和Bi/TiO_(2)的1.7和1.3倍。 展开更多
关键词 Bi/tio_(2)∶Sm^(3+)复合纤维 洛美沙星 表面等离子体共振 稀土离子掺杂 可见光催化活性
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TiO2-Loaded WO3 Composite Films for Enhancement of Photocurrent Density
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作者 Wen-Gui Wang Li Zhu +1 位作者 Yu-Yan Weng Wen Dong 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第2期112-116,共5页
Titanium dioxide (TiO2) loaded tungsten trioxide (WO3) composite films are prepared by an E-beam vapor system. Associated with the existence of a heterojunction at the interface of TiO2 and WO3, the prepared TiO2-... Titanium dioxide (TiO2) loaded tungsten trioxide (WO3) composite films are prepared by an E-beam vapor system. Associated with the existence of a heterojunction at the interface of TiO2 and WO3, the prepared TiO2-WO3 composite film shows enhanced photocurrent density, four times than the pure WO3 film illuminated under xenon lamp, and higher incident-photon-to-current conversion e^ciency. By varying the initial TiO2 film thickness, such composite structures could be optimized to obtain the highest photocurrent density. We believe that thin TiO2 films improve the light response and increase the surface roughness of WO3 films. Furthermore, the existence of the heterojunction results in the e^cient charge carriers' separation, transfer process, and a lower recombination of electron-hole pairs, which is beneficial for the enhancement of photocurrent density. 展开更多
关键词 tio2-Loaded wo3 composite Films for Enhancement of Photocurrent Density FTO
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Experimental and Computational Study of the Microwave Absorption Properties of Recycled α-Fe2O3/OPEFB Fiber/PCL Multi-Layered Composites
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作者 Ebenezer Ekow Mensah Raba’ah Syahidah Azis Zulkifly Abbas 《Journal of Materials Science and Chemical Engineering》 2022年第3期30-41,共12页
The aim of this study was to fabricate multi-layered recycled α-Fe<sub>2</sub>O<sub>3</sub>/OPEFB fiber/PCL composites for microwave absorbing applications in the 1 - 4 GHz frequency range. Th... The aim of this study was to fabricate multi-layered recycled α-Fe<sub>2</sub>O<sub>3</sub>/OPEFB fiber/PCL composites for microwave absorbing applications in the 1 - 4 GHz frequency range. The multi-layered composites were 6 mm thick and each consisted of a 2 mm thick layer of recycled α-Fe<sub>2</sub>O<sub>3</sub>/PCL composites at various loadings (5 wt% - 25 wt%) of 16.2 nm recycled α-Fe<sub>2</sub>O<sub>3</sub> nanofiller, placed between two layers of 2 mm thick OPEFB fiber/PCL composites blended at a fixed ratio of 7:3. The real (ε') and imaginary (ε") components of the relative complex permittivity were measured using the open-ended coaxial probe technique and the values obtained were applied as inputs for the Finite Element Method to calculate the reflection coefficient magnitudes from which the reflection loss (RL) properties were determined. Both ε' and ε" increased linearly with recycled α-Fe<sub>2</sub>O<sub>3</sub> nanofiller content and the values of ε' varied between 3.0 and 3.9 while the ε" values ranged between 0.26 and 0.64 within 1 - 4 GHz. The RL (dB) showed the most prominent values within the 1.38 - 1.46 GHz band with a minimum of -38 dB attained by the 25 wt% composite. Another batch of minimum values occurred in the 2.39 - 3.49 GHz range with the lowest of -25 dB at 2.8 GHz. The recycled α-Fe<sub>2</sub>O<sub>3</sub>/OPEFB fiber/PCL multi-layered composites are promising materials that can be engineered for solving noise problems in the 1 - 4 GHz range. 展开更多
关键词 Multi-Layered composites Recycled α-Fe2O3 Reflection Loss OPEFB fiber Relative Complex Permittivity
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TiO2-PES Fibrous Composite Material for Ammonia Removal Using UV-A Photocatalyst
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作者 Anh Phuong Le Thi Masaru Ohshiro Takaomi Kobayashi 《Journal of Materials Science and Chemical Engineering》 2024年第1期1-19,共19页
This study focused on the development and characterization of TiO<sub>2</sub>-PES composite fibers with varying TiO<sub>2</sub> loading amounts using a phase inversion process. The resulting co... This study focused on the development and characterization of TiO<sub>2</sub>-PES composite fibers with varying TiO<sub>2</sub> loading amounts using a phase inversion process. The resulting composite fibers exhibited a sponge-like structure with embedded TiO<sub>2</sub> nanoparticles within a polymer matrix. Their photocatalytic performance for ammonia removal from aqueous solutions under UV-A light exposure was thoroughly investigated. The findings revealed that PeTi8 composite fibers displayed superior adsorption capacity compared to other samples. Moreover, the study explored the impact of pH, light intensity, and catalyst dosage on the photocatalytic degradation of ammonia. Adsorption equilibrium isotherms closely followed the Langmuir model, with the results indicating a correlation between qm values of 2.49 mg/g and the porous structure of the adsorbents. The research underscored the efficacy of TiO<sub>2</sub> composite fibers in the photocatalytic removal of aqueous under  UV-A light. Notably, increasing the distance between the photocatalyst and the light source resulted in de-creased hydroxyl radical concentration, influencing photocatalytic efficiency. These findings contribute to our understanding of TiO<sub>2</sub> composite fibers as promising photocatalysts for ammonia removal in water treatment applications. 展开更多
关键词 Ammonia Removal PHOTOCATALYST tio2-PES composite fiber Fibrous Material
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Enhanced thermoelectric performance of Bi2Se3/TiO2 composite 被引量:6
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作者 Yu-Xi Yang Ye-Hao Wu +3 位作者 Qi Zhang Gao-Shao Cao Tie-Jun Zhu Xin-Bing Zhao 《Rare Metals》 SCIE EI CAS CSCD 2020年第8期887-894,共8页
Bi2(Te,Se)3 alloys are conventional commercial thermoelectric materials for solid-state refrigeration around room temperature.In recent years,much attention has been paid to various advanced thermoelectric composite m... Bi2(Te,Se)3 alloys are conventional commercial thermoelectric materials for solid-state refrigeration around room temperature.In recent years,much attention has been paid to various advanced thermoelectric composite materials due to the unique thermoelectric properties.In this work,Bi2Se3/TiO2 composites were prepared by hot pressing the plate-like Bi2Se3 powders coated in situ with hydrolyzed hytetabutyl-n-butyl titanate(TNBT),and therefore numerous TiO2 in micrometer size could be formed on the interface of Bi2Se3 grains.The carrier concentration in Bi2Se3 matrix is optimized subject to the addition of n-type semiconductor TiO2,contributing to a significant improved power factor.In the meantime,the lattice thermal conductivity is also suppressed due to the enhanced phonon scattering at Bi2Se3/TiO2 interface and amorphous TiO2 particles.As a consequence,a peak figure of merit(zT)of 0.41 is obtained at 525 K in Bi2Se3/15 mol%TiO2 composites,nearly 50%augment over the pristine Bi2Se3 binary compound. 展开更多
关键词 Bi2(Te Se)3 Thermoelectric materials tio2 composite
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Preparation and Photocatalytic Activity of Ce, H3PW12O40 co-doped TiO2 Hollow Fibers 被引量:3
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作者 Shu-hua Yao Shuang Chen Zhong-liang Shi 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第3期343-349,共7页
A series of Ce, H3PW12O40 co-doped TiO2 hollow fibers photocatalysts have been prepared by sol-gel method using ammonium ceric nitrate, H3PW12O40 and tetrabutyltitanate as precursors and cotton fibers as template, fol... A series of Ce, H3PW12O40 co-doped TiO2 hollow fibers photocatalysts have been prepared by sol-gel method using ammonium ceric nitrate, H3PW12O40 and tetrabutyltitanate as precursors and cotton fibers as template, followed by calcination at 500 ℃ in N2 atmosphere for 2 h. Scanning electron microscopy, X-ray diffraction, nitrogen adsorption-desorption mea- surements, and UV-Vis spectroscopy are employed to characterize the morphology, crystal structure, surface structure, and optical absorption properties of the samples. The photo- catalytic performance of the samples has been studied by photodegradation phenol in water under UV and visible light irradiation. The results show that the TiO2 fiber materials have hollow structures, and the co-doped TiO2 hollow fibers exhibit higher photocatalytic activities for the degradation of phenol than un-doped, single-doped TiO2 hollow fibers under UV and visible light. In addition, the recyclability of co-doped TiO2 fibers is also confirmed that the TiO2 fiber retains ca. 90% of its activity after being used four times. It is shown that the co-doped TiO2 fibers can be activated by visible light and may be potentially applied to the treatment of water contaminated by organic pollutants. The synergistic effect of Ce and H3PW12O40 co-doping plays an important role in improving the photocatalytic activity. 展开更多
关键词 tio2 hollow fibers Ce and H3PW12O40 co-doping Photocatalytic activity Template method PHENOL
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Fabrication of Bi_2O_3/TiO_2nanocomposites and their applications to the degradation of pollutants in air and water under visible-light 被引量:7
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作者 Ashok Kumar Chakraborty Md Emran Hossain +1 位作者 Md Masudur Rhaman K M A Sobahan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第2期458-465,共8页
A nanoheterojunction composite photocatalyst Bi2O3/TiO2 working under visible-light (λ≥ 420 nm) was prepared by combining two semiconductors Bi2O3 and TiO2 varying the Bi2O3/TiO2 molar ratio. Maleic acid was emplo... A nanoheterojunction composite photocatalyst Bi2O3/TiO2 working under visible-light (λ≥ 420 nm) was prepared by combining two semiconductors Bi2O3 and TiO2 varying the Bi2O3/TiO2 molar ratio. Maleic acid was employed as an organic binder to unite Bi2O3 and TiO2 nanoparticles. The SEM, TEM, XRD and diffuse reflectance spectra were utilized to characterize the prepared Bi2O3/TiO2 nanoheterojunction. The nanocomposite exhibited unusual high photocatalytic activity in decomposing 2-propanol in gas phase and phenol in aqueous phase and, evolution of CO2 under visible light irradiation while the end members exhibited low photocatalytic activity. The composite was optimized to 5 mol% Bi2O3/TiO2. The remarkable high photocatalytic efficiency originates from the unique relative energy band position of Bi2O3 and TiO2 as well as the absorption of visible light by Bi2O3. 展开更多
关键词 nanoheterojunction Bi2O3/tio2 composite photocatalyst pollutants visible-light
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国产Al_(2)O_(3f)/Al_(2)O_(3)复合材料的室温和1000℃拉伸性能 被引量:1
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作者 张珂 许平 +5 位作者 张超 李陈晨 应雯清 邢宁 李玫 张程煜 《材料工程》 北大核心 2025年第1期195-201,共7页
连续氧化铝纤维增强氧化铝复合材料(Al_(2)O_(3f)/Al_(2)O_(3))是发展高性能航空发动机热端部件的理想材料。本工作研究了国产Al_(2)O_(3f)/Al_(2)O_(3)复合材料的室温和1000℃拉伸力学性能,使用SEM观察拉伸试样的微观形貌和断口形貌,使... 连续氧化铝纤维增强氧化铝复合材料(Al_(2)O_(3f)/Al_(2)O_(3))是发展高性能航空发动机热端部件的理想材料。本工作研究了国产Al_(2)O_(3f)/Al_(2)O_(3)复合材料的室温和1000℃拉伸力学性能,使用SEM观察拉伸试样的微观形貌和断口形貌,使用TEM观察纤维的微观结构,采用Weibull分布统计分析抗拉强度,利用纤维推入法得到纤维/基体界面剪切强度。结果表明,国产Al_(2)O_(3f)/Al_(2)O_(3)复合材料室温抗拉强度为(257±31)MPa,1000℃的抗拉强度为室温的78%,已达到国际Nextel610/Al_(2)O_(3)水平。研究发现,界面结合强度是影响抗拉强度的主要因素。界面结合强度较低,纤维拔出长且分散,抗拉强度高;界面结合强度较高,发生纤维束断裂,且纤维拔出变短,抗拉强度低。 展开更多
关键词 氧化铝纤维 Al_(2)O_(3f)/Al_(2)O_(3)复合材料 拉伸性能 强度分散性 界面结合强度
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WO_3对MnO_x/TiO_2低温脱硝SCR催化剂的改性研究 被引量:17
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作者 张亚平 汪小蕾 +3 位作者 孙克勤 沈凯 徐海涛 周长城 《燃料化学学报》 EI CAS CSCD 北大核心 2011年第10期782-786,共5页
以醋酸锰为前驱物通过浸渍法制备了MnOx/TiO2催化剂,用WO3对载体进行改性制得一系列MnOx-WO3/TiO2催化剂,采用X射线衍射(XRD)、比表面积测定(BET)、拉曼光谱(LRS)、原位红外(FT-IR)光谱等表征技术进行相关的微观表征分析,同时在模拟氨... 以醋酸锰为前驱物通过浸渍法制备了MnOx/TiO2催化剂,用WO3对载体进行改性制得一系列MnOx-WO3/TiO2催化剂,采用X射线衍射(XRD)、比表面积测定(BET)、拉曼光谱(LRS)、原位红外(FT-IR)光谱等表征技术进行相关的微观表征分析,同时在模拟氨气选择性催化还原NOx(NH3-SCR)的反应条件下对催化剂的脱硝反应活性进行了考察。研究表明,添加5%的WO3拓展了载体的比表面积,提高了催化剂的抗热性,增加了催化剂表面的Brnsted酸位,拓宽其选择性催化还原脱硝活性温度窗口,对MnOx/TiO2催化剂有很好的改性作用;先钨后锰的负载顺序优于先锰后钨;随着温度的升高,化学催化反应速率提高,催化剂表面NH3吸附峰呈减弱或消失趋势,故催化剂脱硝活性温度曲线呈中间高、两头低。 展开更多
关键词 wo3 MnOx/tio2催化剂 低温SCR 负载顺序
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固体超强酸催化剂SO_4^(2-)/TiO_2-WO_3的制备及其催化性能研究 被引量:30
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作者 杨水金 白爱民 +1 位作者 余协卿 孙聚堂 《有机化学》 SCIE CAS CSCD 北大核心 2004年第10期1262-1266,共5页
制备了固体超强酸催化剂SO2 -4/TiO2 WO3 ,并以丁酸丁酯的合成作为探针反应 ,系统考察了WO3 的含量、硫酸浸渍浓度、焙烧温度等制备条件对SO2 -4/TiO2 WO3 催化活性的影响 .实验表明 :制备催化剂的适宜条件为m(H2 WO4) =12 5 % ,硫... 制备了固体超强酸催化剂SO2 -4/TiO2 WO3 ,并以丁酸丁酯的合成作为探针反应 ,系统考察了WO3 的含量、硫酸浸渍浓度、焙烧温度等制备条件对SO2 -4/TiO2 WO3 催化活性的影响 .实验表明 :制备催化剂的适宜条件为m(H2 WO4) =12 5 % ,硫酸浸渍浓度为 1 0mol·L-1,焙烧温度为 5 80℃ ,活化时间 3h .利用优化条件下制备的催化剂SO2 -4/TiO2 WO3 催化合成缩醛 (酮 ) ,在醛 /酮与二元醇 (乙二醇 ,1,2 丙二醇 )的投料摩尔比为 1∶1 5 ,催化剂的用量占反应物总投料质量的 0 5 % ,反应时间为 1h条件下 ,2 甲基 2 乙氧羰甲基 1,3 二氧环戊烷的收率为 78 7% ,2 ,4 二甲基 2 乙氧羰甲基 1,3 二氧环戊烷的收率为 83 0 % ,环己酮 -乙二醇缩酮的收率为 85 9% ,环己酮 1,2 丙二醇缩酮的收率为 84 6% ,丁酮 -乙二醇缩酮的收率为70 7% ,丁酮 1,2 丙二醇缩酮的收率为 88 3 % ,2 丙基 1,3 二氧环戊烷的收率为 80 6% ,4 甲基 2 丙基 1,3 二氧环戊烷的收率为 79 6% ,2 异丙基 1,3 二氧环戊烷的收率为 64 2 % ,4 甲基 2 异丙基 1,3 二氧环戊烷的收率为 83 3 % ,2 苯基 1,3 二氧环戊烷的收率为 75 3 % ,4 甲基 2 苯基 1,3 二氧环戊烷的收率为 95 1% . 展开更多
关键词 固体超强酸催化剂 制备 催化性能 缩酮 缩醛 丁酸丁酯
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包覆型催化剂WO_3-TiO_2的制备及其光催化性能 被引量:9
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作者 童海霞 陈启元 +3 位作者 尹周澜 胡慧萍 李洁 赵理 《中国有色金属学报》 EI CAS CSCD 北大核心 2008年第4期682-687,共6页
以钛酸丁酯为钛源,采用水解法制备金红石型TiO2粉体,用浸渍法将制备的TiO2粉体包覆不同浓度的WO3(记为WO3-TiO2),并采用X射线衍射(XRD)、拉曼光谱(LRS)、透射电镜(TEM)和紫外?可见漫反射光谱(DRS)等手段对所得的光催化剂进行了表征。以... 以钛酸丁酯为钛源,采用水解法制备金红石型TiO2粉体,用浸渍法将制备的TiO2粉体包覆不同浓度的WO3(记为WO3-TiO2),并采用X射线衍射(XRD)、拉曼光谱(LRS)、透射电镜(TEM)和紫外?可见漫反射光谱(DRS)等手段对所得的光催化剂进行了表征。以紫外光为光源,Fe3+为电子牺牲剂,包覆型WO3-TiO2粉体为光催化剂,通过光催化分解水析氧实验,研究催化剂的光催化活性。结果表明:WO3包覆能显著提高TiO2的光催化活性,在12 h内,包覆2%WO3的TiO2光催化分解水产氧速率最高,达到约420μmol/(L.h)。 展开更多
关键词 金红石型tio2 wo3 光催化 析氧
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整体式V_2O_5-WO_3/TiO_2-ZrO_2催化剂用于NH_3选择性催化还原NO_x 被引量:10
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作者 李鹏 张亚平 +4 位作者 肖睿 沈凯 孙克勤 徐海涛 周长城 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2013年第4期1719-1726,共8页
通过共沉淀法制备不同锆掺杂量的钛锆复合载体,用分步浸渍法先后浸渍WO3和V2O5得到一系列V2O5-WO3/TiO2-ZrO2催化剂样品,采用X线衍射(XRD)、比表面积测定(BET)、高分辨率透射电子显微镜(HRTEM),程序升温还原(TPR)等表征技术进行相关的... 通过共沉淀法制备不同锆掺杂量的钛锆复合载体,用分步浸渍法先后浸渍WO3和V2O5得到一系列V2O5-WO3/TiO2-ZrO2催化剂样品,采用X线衍射(XRD)、比表面积测定(BET)、高分辨率透射电子显微镜(HRTEM),程序升温还原(TPR)等表征技术进行相关的表征分析,同时在模拟氨气选择性催化还原NOx(NH3-SCR)的反应条件下对催化剂的脱硝反应活性进行考察。研究结果表明:ZrO2含量为50%(摩尔分数)的催化剂具有较好的热稳定性和较宽的活性窗口。模拟烟气中含有0.08%(体积分数)的SO2时,SO2对所研究催化剂的NO脱除具有一定的促进作用。复合载体Ti0.5Zr0.5O2呈无定形态,具有较大的比表面积和孔容,微粒大小均匀,表面分散性良好;WO3和V2O5高度分散在载体的表面;ZrO2的掺入有利于提高催化剂的还原性能。 展开更多
关键词 V2O5 wo3 tio2-ZRO2 催化还原 抗SO2
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制备工艺对WO_3/TiO_2薄膜可见光催化活性的影响 被引量:11
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作者 张琦 李新军 +2 位作者 李芳柏 王良焱 梁园园 《中国有色金属学报》 EI CAS CSCD 北大核心 2002年第6期1299-1303,共5页
采用磁控溅射技术在浸渍提拉法制得的TiO2 薄膜上溅射WO3 层 ,通过不同制备工艺控制W在TiO2晶体中的分布。UV VIS透射光谱表明 ,在可见光范围内溅射有WO3 层的薄膜有不同程度的吸收光谱红移现象。并理论计算出带隙能 ,溅射WO3 层使薄膜... 采用磁控溅射技术在浸渍提拉法制得的TiO2 薄膜上溅射WO3 层 ,通过不同制备工艺控制W在TiO2晶体中的分布。UV VIS透射光谱表明 ,在可见光范围内溅射有WO3 层的薄膜有不同程度的吸收光谱红移现象。并理论计算出带隙能 ,溅射WO3 层使薄膜的带隙能变小。甲基橙光催化降解实验表明 ,以焙烧—溅射—热处理 5h工艺制备的WO3 /TiO2 薄膜可见光活性最佳 ,W从薄膜表面到内层的浓度递减分布。讨论了不同制备工艺引起的W在薄膜内部的不同分布对光催化活性的影响。 展开更多
关键词 制备工艺 wo3/tio2薄膜 可见光催化活性 二氧化钛 磁控溅射 氧化钨 半导体
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WO_3对TiO_2粉体晶型转变的影响(英文) 被引量:6
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作者 朱振峰 何选盟 +1 位作者 赵毅 任强 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2010年第5期771-774,共4页
以TiO2为原料,通过引入WO3添加剂,经不同温度煅烧后得到钨掺杂的TiO2粉体。利用XRD和SEM等测试手段,研究煅烧温度、WO3引入量对TiO2粉体晶型转变的影响,并对其机制进行探讨。结果表明:WO3促进了TiO2从锐钛矿向金红石的转变,降低了TiO2... 以TiO2为原料,通过引入WO3添加剂,经不同温度煅烧后得到钨掺杂的TiO2粉体。利用XRD和SEM等测试手段,研究煅烧温度、WO3引入量对TiO2粉体晶型转变的影响,并对其机制进行探讨。结果表明:WO3促进了TiO2从锐钛矿向金红石的转变,降低了TiO2的晶型转变温度,随着WO3引入量的增加,促进作用增强。引入的WO3以两种形式促进TiO2的晶型转变:一种是Wn+进入TiO2晶格置换Ti4+而促进了晶型转变;另一种是WO3和TiO2发生氧化还原反应,促进了TiO2的晶型转变。 展开更多
关键词 wo3 tio2 晶型转变
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WO_3/TiO_2复合材料的制备及对甲醛的光催化降解研究 被引量:5
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作者 董金龙 史艳茹 +2 位作者 任跃红 牛俊杰 王尚义 《中北大学学报(自然科学版)》 CAS 北大核心 2014年第2期167-172,共6页
以三氧化钨粉体和钛酸四丁酯为原料,采用溶胶-凝胶法制备WO3/TiO2复合材料;以紫外灯为光源,甲醛的光催化降解为模型反应,考查了热处理温度和样品的组分对其形貌、晶型及降解甲醛的光催化性能的影响和动力学研究;采用X射线衍射、IR光谱... 以三氧化钨粉体和钛酸四丁酯为原料,采用溶胶-凝胶法制备WO3/TiO2复合材料;以紫外灯为光源,甲醛的光催化降解为模型反应,考查了热处理温度和样品的组分对其形貌、晶型及降解甲醛的光催化性能的影响和动力学研究;采用X射线衍射、IR光谱、UV光谱手段对其结构进行了表征.研究结果表明:在热处理温度为500℃,WO3与TiO2的摩尔比为2%时,该催化剂对甲醛的降解率达到最高.光催化降解甲醛的动力学研究表明,该反应属于一级反应. 展开更多
关键词 光催化 wo3 tio2复合材料 制备 甲醛
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新型WO3/TiO2纳米管催化剂的合成及其在环戊烯选择氧化反应中的性能研究 被引量:5
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作者 杨新丽 戴维林 +2 位作者 高瑞华 沈晚晴 范康年 《化学学报》 SCIE CAS CSCD 北大核心 2008年第12期1391-1398,共8页
采用水热合成法以P25为原料制备了介孔TiO2纳米管,并根据TEM和XPS表征结果对其形成机理进行了初步分析.然后,以制备出的介孔TiO2纳米管为载体,钨酸铵为钨源,采用传统浸渍方法制备了介孔WO3/TiO2纳米管催化剂.利用N2吸附,TEM,XRD,XPS及Ra... 采用水热合成法以P25为原料制备了介孔TiO2纳米管,并根据TEM和XPS表征结果对其形成机理进行了初步分析.然后,以制备出的介孔TiO2纳米管为载体,钨酸铵为钨源,采用传统浸渍方法制备了介孔WO3/TiO2纳米管催化剂.利用N2吸附,TEM,XRD,XPS及Raman等手段对固载后的多相催化剂进行了表征,并研究了催化剂在环戊烯选择氧化制备戊二醛反应中的催化性能.结果表明,在介孔20%WO3/TiO2纳米管催化下环戊烯的转化率达97.9%,戊二醛的选择性高达69.3%.钨物种以高度分散状态存在于催化剂中,并与载体间存在着较强的相互作用,使得钨的溶脱量很小,脱落的钨对反应几乎没有影响.另外,催化剂具有较高的稳定性,可以重复套用7次.失活后的催化剂可通过简单焙烧的方式再生. 展开更多
关键词 介孔tio2纳米管 wo3/tio2纳米管催化剂 环戊烯 选择氧化 过氧化氢 戊二醛
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